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1.	Achberger, Christine, 1968, et al. (författare) State of the Climate in 2011 2012 Ingår i: Bulletin of the American Meteorological Society. - 0003-0007. ; 93:7 Tidskriftsartikel (refereegranskat)abstract Large-scale climate patterns influenced temperature and weather patterns around the globe in 2011. In particular, a moderate-to-strong La Nina at the beginning of the year dissipated during boreal spring but reemerged during fall. The phenomenon contributed to historical droughts in East Africa, the southern United States, and northern Mexico, as well the wettest two-year period (2010-11) on record for Australia, particularly remarkable as this follows a decade-long dry period. Precipitation patterns in South America were also influenced by La Nina. Heavy rain in Rio de Janeiro in January triggered the country's worst floods and landslides in Brazil's history. The 2011 combined average temperature across global land and ocean surfaces was the coolest since 2008, but was also among the 15 warmest years on record and above the 1981-2010 average. The global sea surface temperature cooled by 0.1 degrees C from 2010 to 2011, associated with cooling influences of La Nina. Global integrals of upper ocean heat content for 2011 were higher than for all prior years, demonstrating the Earth's dominant role of the oceans in the Earth's energy budget. In the upper atmosphere, tropical stratospheric temperatures were anomalously warm, while polar temperatures were anomalously cold. This led to large springtime stratospheric ozone reductions in polar latitudes in both hemispheres. Ozone concentrations in the Arctic stratosphere during March were the lowest for that period since satellite records began in 1979. An extensive, deep, and persistent ozone hole over the Antarctic in September indicates that the recovery to pre-1980 conditions is proceeding very slowly. Atmospheric carbon dioxide concentrations increased by 2.10 ppm in 2011, and exceeded 390 ppm for the first time since instrumental records began. Other greenhouse gases also continued to rise in concentration and the combined effect now represents a 30% increase in radiative forcing over a 1990 baseline. Most ozone depleting substances continued to fall. The global net ocean carbon dioxide uptake for the 2010 transition period from El Nino to La Nina, the most recent period for which analyzed data are available, was estimated to be 1.30 Pg C yr(-1), almost 12% below the 29-year long-term average. Relative to the long-term trend, global sea level dropped noticeably in mid-2010 and reached a local minimum in 2011. The drop has been linked to the La Nina conditions that prevailed throughout much of 2010-11. Global sea level increased sharply during the second half of 2011. Global tropical cyclone activity during 2011 was well-below average, with a total of 74 storms compared with the 1981-2010 average of 89. Similar to 2010, the North Atlantic was the only basin that experienced above-normal activity. For the first year since the widespread introduction of the Dvorak intensity-estimation method in the 1980s, only three tropical cyclones reached Category 5 intensity level-all in the Northwest Pacific basin. The Arctic continued to warm at about twice the rate compared with lower latitudes. Below-normal summer snowfall, a decreasing trend in surface albedo, and above-average surface and upper air temperatures resulted in a continued pattern of extreme surface melting, and net snow and ice loss on the Greenland ice sheet. Warmer-than-normal temperatures over the Eurasian Arctic in spring resulted in a new record-low June snow cover extent and spring snow cover duration in this region. In the Canadian Arctic, the mass loss from glaciers and ice caps was the greatest since GRACE measurements began in 2002, continuing a negative trend that began in 1987. New record high temperatures occurred at 20 m below the land surface at all permafrost observatories on the North Slope of Alaska, where measurements began in the late 1970s. Arctic sea ice extent in September 2011 was the second-lowest on record, while the extent of old ice (four and five years) reached a new record minimum that was just 19% of normal. On the opposite pole, austral winter and spring temperatures were more than 3 degrees C above normal over much of the Antarctic continent. However, winter temperatures were below normal in the northern Antarctic Peninsula, which continued the downward trend there during the last 15 years. In summer, an all-time record high temperature of -12.3 degrees C was set at the South Pole station on 25 December, exceeding the previous record by more than a full degree. Antarctic sea ice extent anomalies increased steadily through much of the year, from briefly setting a record low in April, to well above average in December. The latter trend reflects the dispersive effects of low pressure on sea ice and the generally cool conditions around the Antarctic perimeter.
2.	Blunden, Jessica, et al. (författare) State of the Climate in 2012 2013 Ingår i: Bulletin of The American Meteorological Society - (BAMS). - 0003-0007 .- 1520-0477. ; 94:8, s. S1-S258 Tidskriftsartikel (refereegranskat)abstract For the first time in serveral years, the El Nino-Southern Oscillation did not dominate regional climate conditions around the globe. A weak La Ni a dissipated to ENSOneutral conditions by spring, and while El Nino appeared to be emerging during summer, this phase never fully developed as sea surface temperatures in the eastern conditions. Nevertheless, other large-scale climate patterns and extreme weather events impacted various regions during the year. A negative phase of the Arctic Oscillation from mid-January to early February contributed to frigid conditions in parts of northern Africa, eastern Europe, and western Asia. A lack of rain during the 2012 wet season led to the worst drought in at least the past three decades for northeastern Brazil. Central North America also experienced one of its most severe droughts on record. The Caribbean observed a very wet dry season and it was the Sahel's wettest rainy season in 50 years. Overall, the 2012 average temperature across global land and ocean surfaces ranked among the 10 warmest years on record. The global land surface temperature alone was also among the 10 warmest on record. In the upper atmosphere, the average stratospheric temperature was record or near-record cold, depending on the dataset. After a 30-year warming trend from 1970 to 1999 for global sea surface temperatures, the period 2000-12 had little further trend. This may be linked to the prevalence of La Ni a-like conditions during the 21st century. Heat content in the upper 700 m of the ocean remained near record high levels in 2012. Net increases from 2011 to 2012 were observed at 700-m to 2000-m depth and even in the abyssal ocean below. Following sharp decreases in to the effects of La Ni a, sea levels rebounded to reach records highs in 2012. The increased hydrological cycle seen in recent years continued, with more evaporation in drier locations and more precipitation in rainy areas. In a pattern that has held since 2004, salty areas of the ocean surfaces and subsurfaces were anomalously salty on average, while fresher areas were anomalously fresh. Global tropical cyclone activity during 2012 was near average, with a total of 84 storms compared with the 1981-2010 average of 89. Similar to 2010 and 2011, the North Atlantic was the only hurricane basin that experienced above-normal activity. In this basin, Sandy brought devastation to Cuba and parts of the eastern North American seaboard. All other basins experienced either near-or below-normal tropical cyclone activity. Only three tropical cyclones reached Category 5 intensity-all in Bopha became the only storm in the historical record to produce winds greater than 130 kt south of 7 N. It was also the costliest storm to affect the Philippines and killed more than 1000 residents. Minimum Arctic sea ice extent in September and Northern Hemisphere snow cover extent in June both reached new record lows. June snow cover extent is now declining at a faster rate (-17.6% per decade) than September sea ice extent (-13.0% per decade). Permafrost temperatures reached record high values in northernmost Alaska. A new melt extent record occurred on 11-12 July on the Greenland ice sheet; 97% of the ice sheet showed some form of melt, four times greater than the average melt for this time of year. The climate in Antarctica was relatively stable overall. The largest maximum sea ice extent since records begain in 1978 was observed in September 2012. In the stratosphere, warm air led to the second smallest ozone hole in the past two decades. Even so, the springtime ozone layer above Antarctica likely will not return to its early 1980s state until about 2060. Following a slight decline associated with the global 2 emissions from fossil fuel combustion and cement production reached a record 9.5 +/- 0.5 Pg C in 2011 and a new record of 9.7 +/- 0.5 Pg C is estimated for 2012. Atmospheric CO2 concentrations increased by 2.1 ppm in 2012, to 392.6 ppm. In spring 2012, 2 concentration exceeded 400 ppm at 7 of the 13 Arctic observation sites. Globally, other greenhouse gases including methane and nitrous oxide also continued to rise in concentration and the combined effect now represents a 32% increase in radiative forcing over a 1990 baseline. Concentrations of most ozone depleting substances continued to fall.
3.	Saunois, M., et al. (författare) The global methane budget 2000–2012 2016 Ingår i: Earth System Science Data. - : Copernicus GmbH. - 1866-3508 .- 1866-3516. ; 8:2, s. 697-751 Tidskriftsartikel (refereegranskat)abstract The global methane (CH4) budget is becoming an increasingly important component for managing realistic pathways to mitigate climate change. This relevance, due to a shorter atmospheric lifetime and a stronger warming potential than carbon dioxide, is challenged by the still unexplained changes of atmospheric CH4 over the past decade. Emissions and concentrations of CH4 are continuing to increase, making CH4 the second most important human-induced greenhouse gas after carbon dioxide. Two major difficulties in reducing uncertainties come from the large variety of diffusive CH4 sources that overlap geographically, and from the destruction of CH4 by the very short-lived hydroxyl radical (OH). To address these difficulties, we have established a consortium of multi-disciplinary scientists under the umbrella of the Global Carbon Project to synthesize and stimulate research on the methane cycle, and producing regular (∼ biennial) updates of the global methane budget. This consortium includes atmospheric physicists and chemists, biogeochemists of surface and marine emissions, and socio-economists who study anthropogenic emissions. Following Kirschke et al. (2013), we propose here the first version of a living review paper that integrates results of top-down studies (exploiting atmospheric observations within an atmospheric inverse-modelling framework) and bottom-up models, inventories and data-driven approaches (including process-based models for estimating land surface emissions and atmospheric chemistry, and inventories for anthropogenic emissions, data-driven extrapolations). For the 2003–2012 decade, global methane emissions are estimated by top-down inversions at 558 Tg CH4 yr−1, range 540–568. About 60 % of global emissions are anthropogenic (range 50–65 %). Since 2010, the bottom-up global emission inventories have been closer to methane emissions in the most carbon-intensive Representative Concentrations Pathway (RCP8.5) and higher than all other RCP scenarios. Bottom-up approaches suggest larger global emissions (736 Tg CH4 yr−1, range 596–884) mostly because of larger natural emissions from individual sources such as inland waters, natural wetlands and geological sources. Considering the atmospheric constraints on the top-down budget, it is likely that some of the individual emissions reported by the bottom-up approaches are overestimated, leading to too large global emissions. Latitudinal data from top-down emissions indicate a predominance of tropical emissions (∼ 64 % of the global budget, < 30° N) as compared to mid (∼ 32 %, 30–60° N) and high northern latitudes (∼ 4 %, 60–90° N). Top-down inversions consistently infer lower emissions in China (∼ 58 Tg CH4 yr−1, range 51–72, −14 %) and higher emissions in Africa (86 Tg CH4 yr−1, range 73–108, +19 %) than bottom-up values used as prior estimates. Overall, uncertainties for anthropogenic emissions appear smaller than those from natural sources, and the uncertainties on source categories appear larger for top-down inversions than for bottom-up inventories and models. The most important source of uncertainty on the methane budget is attributable to emissions from wetland and other inland waters. We show that the wetland extent could contribute 30–40 % on the estimated range for wetland emissions. Other priorities for improving the methane budget include the following: (i) the development of process-based models for inland-water emissions, (ii) the intensification of methane observations at local scale (flux measurements) to constrain bottom-up land surface models, and at regional scale (surface networks and satellites) to constrain top-down inversions, (iii) improvements in the estimation of atmospheric loss by OH, and (iv) improvements of the transport models integrated in top-down inversions. The data presented here can be downloaded from the Carbon Dioxide Information Analysis Center (http://doi.org/10.3334/CDIAC/GLOBAL_METHANE_BUDGET_2016_V1.1) and the Global Carbon Project.
4.	Saunois, M., et al. (författare) Variability and quasi-decadal changes in the methane budget over the period 2000–2012 2017 Ingår i: Atmospheric Chemistry And Physics. - : Copernicus GmbH. - 1680-7316 .- 1680-7324. ; 17:18, s. 11135-11161 Tidskriftsartikel (refereegranskat)abstract Following the recent Global Carbon Project (GCP) synthesis of the decadal methane (CH4) budget over 2000–2012 (Saunois et al., 2016), we analyse here the same dataset with a focus on quasi-decadal and inter-annual variability in CH4 emissions. The GCP dataset integrates results from top-down studies (exploiting atmospheric observations within an atmospheric inverse-modelling framework) and bottom-up models (including process-based models for estimating land surface emissions and atmospheric chemistry), inventories of anthropogenic emissions, and data-driven approaches. The annual global methane emissions from top-down studies, which by construction match the observed methane growth rate within their uncertainties, all show an increase in total methane emissions over the period 2000–2012, but this increase is not linear over the 13 years. Despite differences between individual studies, the mean emission anomaly of the top-down ensemble shows no significant trend in total methane emissions over the period 2000–2006, during the plateau of atmospheric methane mole fractions, and also over the period 2008–2012, during the renewed atmospheric methane increase. However, the top-down ensemble mean produces an emission shift between 2006 and 2008, leading to 22 [16–32] Tg CH4 yr−1 higher methane emissions over the period 2008–2012 compared to 2002–2006. This emission increase mostly originated from the tropics, with a smaller contribution from mid-latitudes and no significant change from boreal regions. The regional contributions remain uncertain in top-down studies. Tropical South America and South and East Asia seem to contribute the most to the emission increase in the tropics. However, these two regions have only limited atmospheric measurements and remain therefore poorly constrained. The sectorial partitioning of this emission increase between the periods 2002–2006 and 2008–2012 differs from one atmospheric inversion study to another. However, all top-down studies suggest smaller changes in fossil fuel emissions (from oil, gas, and coal industries) compared to the mean of the bottom-up inventories included in this study. This difference is partly driven by a smaller emission change in China from the top-down studies compared to the estimate in the Emission Database for Global Atmospheric Research (EDGARv4.2) inventory, which should be revised to smaller values in a near future. We apply isotopic signatures to the emission changes estimated for individual studies based on five emission sectors and find that for six individual top-down studies (out of eight) the average isotopic signature of the emission changes is not consistent with the observed change in atmospheric 13CH4. However, the partitioning in emission change derived from the ensemble mean is consistent with this isotopic constraint. At the global scale, the top-down ensemble mean suggests that the dominant contribution to the resumed atmospheric CH4 growth after 2006 comes from microbial sources (more from agriculture and waste sectors than from natural wetlands), with an uncertain but smaller contribution from fossil CH4 emissions. In addition, a decrease in biomass burning emissions (in agreement with the biomass burning emission databases) makes the balance of sources consistent with atmospheric 13CH4 observations. In most of the top-down studies included here, OH concentrations are considered constant over the years (seasonal variations but without any inter-annual variability). As a result, the methane loss (in particular through OH oxidation) varies mainly through the change in methane concentrations and not its oxidants. For these reasons, changes in the methane loss could not be properly investigated in this study, although it may play a significant role in the recent atmospheric methane changes as briefly discussed at the end of the paper.
5.	Schnadt, J., et al. (författare) Adsorption and charge transfer study of bi-isonicotinic acid on in situ grown anatase TiO2 nanoparticles Annan publikation (övrigt vetenskapligt/konstnärligt)
6.	Bennich, P, et al. (författare) Photoemission study of K on graphite 1999 Ingår i: PHYSICAL REVIEW B-CONDENSED MATTER. - : AMERICAN PHYSICAL SOC. - 0163-1829. ; 59:12, s. 8292-8304 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract The physical and electronic structure of the dispersed and (2 x 2) phases of K/graphite have been characterized by valence and core-level photoemission. Charge transfer from K to graphite is found to occur at all coverages, and includes transfer of charge
7.	Macovez, R., et al. (författare) Electronic surface reconstruction and correlation in the fcc and dimer phases of RbC60 2007 Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 75:19, s. 195424- Tidskriftsartikel (refereegranskat)abstract A combined photoemission and x-ray absorption study of a RbC60 crystalline film is presented. We find evidence for an electronic charge reconstruction of the film surface in both the fcc and the dimer phases of RbC60. We confirm the previous conclusion on less crystalline films that the dimer phase is insulating. Several observations, such as the presence of molecular features in the photoemission spectra, indicate that at least partial electron localization occurs in the high-temperature fcc phase. In the fcc phase, the surface consists in a half-charge C60(111) plane and appears weakly metallic, as found for the bulk. In the dimer phase, the charge reconstruction simply implies the presence of neutral C60 in the surface layer. The identification of neutral molecules in the surface layer drastically improves the agreement between calculations of the electronic density of states and photoelectron spectra in both phases.
8.	O'Shea, J. N., et al. (författare) X-ray photoelectron spectroscopy of low surface concentration mass-selected Ag clusters 2000 Ingår i: J. Chem. Pys.. ; 113, s. 9233-9238 Tidskriftsartikel (refereegranskat)
9.	Sandell, A, et al. (författare) Bonding of an isolated K atom to a surface: Experiment and theory 1997 Ingår i: PHYSICAL REVIEW LETTERS. - : AMER INST PHYSICS. - 0031-9007. ; 78:26, s. 4994-4997 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract We present a new and general technique with which the local properties of the unoccupied states of an adsorbed alkali atom in the low coverage limit can be studied. The method, based on a combination of experimental core level spectroscopy data and calcul
10.	Sandell, A, et al. (författare) Nature of the ns-derived states for an isolated alkali atom on a surface 1999 Ingår i: SURFACE SCIENCE. - : ELSEVIER SCIENCE BV. - 0039-6028. ; 429:1-3, s. 309-319 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract It has recently been shown (for K/graphite) that experimental core level spectroscopy data for adsorbed Ar combined with calculations is a most valuable tool in order to obtain information about the alkali-derived unoccupied density-of-states [A. Sandell
11.	Sandell, A., et al. (författare) Observation of a low-energy adsorbate core-level satellite for CO bonded to palladium : Coordination-dependent effects 1998 Ingår i: Physical Review B (Condensed Matter). - 0163-1829. ; 57:20, s. 13199-13208 Tidskriftsartikel (refereegranskat)abstract A strong low-energy shake-up satellite for CO adsorbed on Pd is observed. The occurrence of the satellite is established for the CO/1 ML Pd/Mo(110) system at a coverage where CO adsorbs exclusively on-top. Comparisons with CO adsorbed on Pd single-crystal surfaces and small supported Pd particles indicate that the strongly increased satellite intensity is due to the decreased CO-Pd interaction strength for on-top adsorbed CO. This can be used to get further insight into the structure and bonding properties of the adsorbate system. Since a low-energy shake-up feature may be misinterpreted as a chemically shifted component, the conclusion is that great care has to be taken in the evaluation of adsorbate core-level spectra for systems with large variations in adsorption strength depending on the adsorbate sites. Large variations in the CO site distribution may furthermore occur depending on the nature of the Pd substrate: Adsorption of CO on 1 ML Pd/Mo(110) leads to an overlayer dominated by an on-top species and, likewise, the CO overlayer formed on small Pd particles after large doses has a large fraction of on-top bonded species. This is in strong contrast to Pd single-crystal surfaces, where CO adsorbed in more highly coordinated sites is abundant.
12.	Saunois, Marielle, et al. (författare) The Global Methane Budget 2000–2017 2020 Ingår i: Earth System Science Data. - : Copernicus GmbH. - 1866-3516 .- 1866-3508. ; 12:3, s. 1561-1623 Tidskriftsartikel (refereegranskat)abstract Understanding and quantifying the global methane (CH4) budget is important for assessing realistic pathways to mitigate climate change. Atmospheric emissions and concentrations of CH4 continue to increase, making CH4 the second most important human-influenced greenhouse gas in terms of climate forcing, after carbon dioxide (CO2). The relative importance of CH4 compared to CO2 depends on its shorter atmospheric lifetime, stronger warming potential, and variations in atmospheric growth rate over the past decade, the causes of which are still debated. Two major challenges in reducing uncertainties in the atmospheric growth rate arise from the variety of geographically overlapping CH4 sources and from the destruction of CH4 by short-lived hydroxyl radicals (OH). To address these challenges, we have established a consortium of multidisciplinary scientists under the umbrella of the Global Carbon Project to synthesize and stimulate new research aimed at improving and regularly updating the global methane budget. Following Saunois et al. (2016), we present here the second version of the living review paper dedicated to the decadal methane budget, integrating results of top-down studies (atmospheric observations within an atmospheric inverse-modelling framework) and bottom-up estimates (including process-based models for estimating land surface emissions and atmospheric chemistry, inventories of anthropogenic emissions, and data-driven extrapolations).For the 2008–2017 decade, global methane emissions are estimated by atmospheric inversions (a top-down approach) to be 576 Tg CH4 yr−1 (range 550–594, corresponding to the minimum and maximum estimates of the model ensemble). Of this total, 359 Tg CH4 yr−1 or ∼ 60 % is attributed to anthropogenic sources, that is emissions caused by direct human activity (i.e. anthropogenic emissions; range 336–376 Tg CH4 yr−1 or 50 %–65 %). The mean annual total emission for the new decade (2008–2017) is 29 Tg CH4 yr−1 larger than our estimate for the previous decade (2000–2009), and 24 Tg CH4 yr−1 larger than the one reported in the previous budget for 2003–2012 (Saunois et al., 2016). Since 2012, global CH4 emissions have been tracking the warmest scenarios assessed by the Intergovernmental Panel on Climate Change. Bottom-up methods suggest almost 30 % larger global emissions (737 Tg CH4 yr−1, range 594–881) than top-down inversion methods. Indeed, bottom-up estimates for natural sources such as natural wetlands, other inland water systems, and geological sources are higher than top-down estimates. The atmospheric constraints on the top-down budget suggest that at least some of these bottom-up emissions are overestimated. The latitudinal distribution of atmospheric observation-based emissions indicates a predominance of tropical emissions (∼ 65 % of the global budget, < 30∘ N) compared to mid-latitudes (∼ 30 %, 30–60∘ N) and high northern latitudes (∼ 4 %, 60–90∘ N). The most important source of uncertainty in the methane budget is attributable to natural emissions, especially those from wetlands and other inland waters.Some of our global source estimates are smaller than those in previously published budgets (Saunois et al., 2016; Kirschke et al., 2013). In particular wetland emissions are about 35 Tg CH4 yr−1 lower due to improved partition wetlands and other inland waters. Emissions from geological sources and wild animals are also found to be smaller by 7 Tg CH4 yr−1 by 8 Tg CH4 yr−1, respectively. However, the overall discrepancy between bottom-up and top-down estimates has been reduced by only 5 % compared to Saunois et al. (2016), due to a higher estimate of emissions from inland waters, highlighting the need for more detailed research on emissions factors. Priorities for improving the methane budget include (i) a global, high-resolution map of water-saturated soils and inundated areas emitting methane based on a robust classification of different types of emitting habitats; (ii) further development of process-based models for inland-water emissions; (iii) intensification of methane observations at local scales (e.g., FLUXNET-CH4 measurements) and urban-scale monitoring to constrain bottom-up land surface models, and at regional scales (surface networks and satellites) to constrain atmospheric inversions; (iv) improvements of transport models and the representation of photochemical sinks in top-down inversions; and (v) development of a 3D variational inversion system using isotopic and/or co-emitted species such as ethane to improve source partitioning.The data presented here can be downloaded from https://doi.org/10.18160/GCP-CH4-2019 (Saunois et al., 2020) and from the Global Carbon Project.
13.	Schnadt, J., Schiessling, J., O'Shea, J.N., Gray, S.M., Patthey, L., Johansson, M.K.J., Shi, M., Krepansky, J., Åhlund, J., Karlsson, P.G., Persson, P., Mårtensson, N., and Brühwiler, P.A. (författare) Structural study of adsorption of isonicotinic acid and related molecules on rutile TiO2(110). I: XAS and STM 2003 Ingår i: Surface Science. ; 540, s. 39- Tidskriftsartikel (refereegranskat)
14.	Kjeldgaard, L., et al. (författare) Local Dephasing and Vibronic Character of Electron States in Solid C60 Annan publikation (övrigt vetenskapligt/konstnärligt)
15.	Käämbre, T., et al. (författare) Resonant inelastic X-ray scattering from solid C60 Annan publikation (övrigt vetenskapligt/konstnärligt)
16.	Käämbre, T., et al. (författare) Resonant Inelastic X-ray Scattering Study of Intermolecular Charge Transfer Rates in K3C60 Annan publikation (övrigt vetenskapligt/konstnärligt)
17.	Patthey, L, et al. (författare) Adsorption of bi-isonicotinic acid on rutile TiO2(110) 1999 Ingår i: JOURNAL OF CHEMICAL PHYSICS. - 0021-9606. ; 110:12, s. 5913-5918 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract Bi-isonicotinic acid (2,2'-bipyridine- 4,4'-dicarboxylic acid) is the ligand of several organometallic dyes, used in photoelectrochemical applications. Therefore the atomic scale understanding of the bonding of this molecule to rutile TiO2(110) should giv
18.	Puglia, C, et al. (författare) A photoemission and XAS study of oxygen coadsorbed with a (2x2) layer of K on graphite 1997 Ingår i: SURFACE SCIENCE. - : ELSEVIER SCIENCE BV. - 0039-6028. ; 383:2-3, s. 149-161 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract We have studied the coadsorption of oxygen with a (2 x 2) monolayer of K on graphite. At least three different adsorption phases for oxygen have been found. Different spectroscopic techniques have been used in order to identify the different oxygen specie
19.	Puglia, C, et al. (författare) XPS and XAS study of oxygen coadsorbed with a dispersed phase of K on graphite 2001 Ingår i: SURFACE SCIENCE. - : ELSEVIER SCIENCE BV. ; 488:1-2 Annan publikation (övrigt vetenskapligt/konstnärligt)abstract The adsorption of O-2 onto a dispersed (low coverage) phase of K on graphite has been characterized by X-ray photoemission and X-ray absorption spectroscopy. We identify two oxygen adsorption phases before physisorbed oxygen appears. The first species dom
20.	Sandell, A, et al. (författare) Electron spectroscopy studies of small deposited metal particles 1995 Ingår i: JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA. - : ELSEVIER SCIENCE BV. ; 76, s. 301-306 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract The Al2O3/NiAl(110) system with and without Pd clusters on the surface has been studied using photoemission of both core and valence levels. Pd has been deposited under various conditions, and changes in the spectra due to differences in growth modes are
21.	Schiessling, J., et al. (författare) Molecular Orbital Components of C60 on Al/(110) Annan publikation (övrigt vetenskapligt/konstnärligt)
22.	Schiessling, J., et al. (författare) Orbital splitting and molecular orientation for C60/Al(110) Annan publikation (övrigt vetenskapligt/konstnärligt)
23.	Schiessling, J., et al. (författare) Surface Electronic Structure of K3C60 Ingår i: Phys. Rev. Lett.. Tidskriftsartikel (refereegranskat)
24.	Schnadt, J, et al. (författare) Adsorption and charge-transfer study of bi-isonicotinic acid on in situ-grown anatase TiO2 nanoparticles 2004 Ingår i: The Journal of Physical Chemistry Part B. - : American Chemical Society (ACS). - 1520-5207 .- 1520-6106. ; 108:10, s. 3114-3122 Tidskriftsartikel (refereegranskat)abstract Bi-isonicotinic acid (2,2'-bipyridine-4,4'-dicarboxylic acid) is an important ligand in the chemistry of organometallic devices. Here, the adsorption of a monolayer of the molecule on in situ-grown anatase TiO2 nanoparticles has been investigated by means of X-ray photoemission spectroscopy and X-ray absorption spectroscopy. The bonding geometry is determined to be 2M-bidentate. Furthermore, resonant core spectroscopies have been used to study the excited-state-dependent electron transfer from the core-excited molecule to the substrate. For an excitation to the lowest unoccupied orbital, the excited electron is localized on the molecule because of a core-excitonic effect. Excitation to the two following unoccupied orbitals leads to a charge transfer on a low-femtosecond time scale. This study shows that there is no essential difference in charge-transfer characteristics, compared to the case of adsorption on the rutile (110) surface, for states degenerate with the conduction band.
25.	Schnadt, J., et al. (författare) Electron Spectroscopy Study of LiC60: Charge Transfer and Dimer Formation 2000 Ingår i: Phys. Rev. B. ; 62, s. 4253-4256 Tidskriftsartikel (refereegranskat)
26.	Schnadt, J., et al. (författare) Experiemental evidence for sub-3-fs charge transfer from an aromatic adsorbate to a semiconductor 2002 Ingår i: Nature. ; 418, s. 620-623 Tidskriftsartikel (refereegranskat)
27.	Schnadt, J., et al. (författare) Structural study of absorption of isonicotinic acid and related molecules on rutile TiO2(110) I.: XAS and STM Annan publikation (övrigt vetenskapligt/konstnärligt)
28.	J. Schiessling, L. Kjeldgaard, T. Balasubramanian, J. Nordgren, and P. A. Brühwiler (författare) Molecular Angular Photoelectron Distribution of Solid C60 2003 Ingår i: Phys. Rev.. ; B:68, s. 205405- Tidskriftsartikel (refereegranskat)
29.	J. Schnadt, J. N. O`Shea, L. Patthey, J. Schiessling, M. Shi, J. Krempasky, J. Åhlund, N. Mårtensson, and P. A, Brühwiler (författare) Structural study of adsorption of isonicotinic acid and related molecules on rutile TiO2(110) II.: XPS 2003 Ingår i: Surf. Sci.. ; :544, s. 74- Tidskriftsartikel (refereegranskat)
30.	Käämbre, Tanel, et al. (författare) Bulk electronic structure of K3C60 as revealed by soft x-rays 2007 Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 75:19, s. 195432- Tidskriftsartikel (refereegranskat)abstract We present C 1s x- ray absorption, x- ray emission, and resonant inelastic x- ray scattering (RIXS ) spectra of single- phase crystalline K3C60. The comparison to valence- band photoelectron spectra from the same sample facilitates identification of the contribution from surface and bulk electronic states in the latter. Bulk- sensitive techniques show that the valence bands of K3C60 and pure C-60 are characterized by spectral features of similar width, in agreement with the predictions of band- structure calculations. Symmetry selectivity in the RIXS process allows us to assign peaks in the C 1s absorption spectrum, demonstrating a close correspondence with pure C-60 also in the conduction band. The symmetry selectivity is as pronounced in K3C60 as in pure C-60, indicating that the local C-60 symmetry is not appreciably affected by the K doping, either in the ground state or intermediate state, on the time scale of 6 fs.
31.	O'Shea, J. N., et al. (författare) Hydrogen-bond induced surface core-level shift in isonicotinic acid 2001 Ingår i: Journal of Physical Chemistry B. - : American Chemical Society (ACS). - 1089-5647 .- 1520-6106 .- 1520-5207. ; 105:10, s. 1917-1920 Tidskriftsartikel (refereegranskat)abstract Intermolecular hydrogen-bonding in thick films of isonicotinic acid evaporated onto rutile TiO2(110) has been investigated with X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS). The rate of deposition is found to be a key factor in overcoming the kinetic barriers to extensive hydrogen-bond formation, which, when present, gives rise to large energy shifts between bulk and surface in both the N1s XPS and XAS. The origin of the surface core-level shift is attributed to the presence of non-hydrogen-bonded nitrogen atoms in the surface layer.
32.	O'Shea, J. N., et al. (författare) Hydrogen-bond induced surface core-level shift in isonicotinic acid 2001 Ingår i: J. Phys. Chem. B. ; 105, s. 1917-1920 Tidskriftsartikel (refereegranskat)
33.	O'Shea, J. N., et al. (författare) Hydrogen-bond induced surface core-level shift in pyridine carboxylic acids 2001 Ingår i: Surface Science. - 0039-6028 .- 1879-2758. ; 486:3, s. 157-166 Tidskriftsartikel (refereegranskat)abstract Intermolecular hydrogen bonding in thick films of pyridine carboxylic acids (isonicotinic; picolinic and bi-isonicotinic acid) evaporated onto rutile TiO2(1 1 0) has been investigated with X-ray photoelectron spectroscopy and X-ray absorption spectroscopy. These molecules are shown to be strongly H-bonded in the condensed phase, and a surface core-level shift is observed due to the presence of non-H-bonded nitrogen atoms in the surface layer. Density functional theory calculations are used to relate the experimental data to the proposed bonding configurations based on the surface termination of the known equilibrium solid-state structure. A kinetic barrier, attributed to the high degree of molecular orientation required for the formation of extended H-bonding networks, has also been investigated.
34.	O'Shea, J. N., et al. (författare) Hydrogen-bond induced surface core-level shift in pyridine carboxylic acids 2001 Ingår i: Surf. Sci.. ; 486, s. 157-166 Tidskriftsartikel (refereegranskat)
35.	Persson, Petter, et al. (författare) N1s x-ray Absorption Study of the Bonding Interaction of Bi-Isonicotinic Acid on Rutile TiO2 (110) 2000 Ingår i: Journal of Chemical Physics. - : AIP Publishing. - 0021-9606 .- 1089-7690. ; 112:9, s. 3945-3948 Tidskriftsartikel (refereegranskat)abstract N1s x-ray absorption spectra of bi-isonicotinic acid (2,28-bipyridine–4,48-dicarboxylic acid! on rutile TiO2(110) have been studied experimentally and quantum chemically. Differences between multilayer and monolayer spectra are explained by the adsorbate bonding to the substrate. A connection to the electronic coupling in dye-sensitized electrochemical devices is made.
36.	Puglia, Carla, et al. (författare) Core level spectroscopy study of N-2 adsorbed on (2x2)K/graphite 1998 Ingår i: SURFACE SCIENCE. - 0039-6028. ; 414:1-2, s. 118-130 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract We report a study of N-2/(2 x 2)K/graphite at 25 K using X-ray photoemission, X-ray absorption (XAS), ultraviolet photoemission, autoionization and Auger spectroscopies. At this temperature me found that N-2 physisorbs. Comparisons with the physisorbed sy
37.	Puglia, C, et al. (författare) New final state in the autoionization decay detected for N-2/(2x2)K/graphite: Relevance for the affinity level of NO on a K monolayer 1998 Ingår i: JOURNAL OF CHEMICAL PHYSICS. - : AMER INST PHYSICS. - 0021-9606. ; 109:4, s. 1209-1211 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract We have observed a new type of charge transfer state in the autoionization spectrum for N-2/(2X2)K/graphite. It can be viewed as a consequence of an important covalent component to the bonding with the surface in the core hole excited state for N-2/(2x2)K
38.	Rudolf, P, et al. (författare) Studies of fullerenes by the excitation, emission, and scattering of electrons 1999 Ingår i: Journal of Electron Spectroscopy and Related Phenomena. - 0368-2048 .- 1873-2526. ; 100:1-3, s. 409-433 Tidskriftsartikel (refereegranskat)abstract This paper presents an overview of how electron spectroscopies have contributed to advances in fullerene research. In particular, we illustrate the vital role these techniques have played in improving our understanding of the importance of strong electronic correlation and of electron-phonon coupling in these materials, in the derivation of electron hopping rates, in providing a direct determination of charge transfer and hybridisation in both fullerene salts and adsorbed fullerenes and in determining the optical gap of these systems. We discuss systems of increasing complexity, starting with C60 in the gas phase and in the solid state, and moving on to C60 salts and to C60 adsorbed on surfaces. Finally we look at both higher fullerenes and fullerenes with a heteroatom either on or inside the cage.
39.	Schiessling, Joachim, 1971- (författare) Angle-Dependent Electron Spectroscopy Studies of C60 Compounds and Carbon Nanotubes 2003 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract Fullerenes have been shown to constitute a prototypical building block for truly nanometer-sized devices and exotic nanounit-based materials, e.g., high-temperature superconductors. This makes the detailed understanding of fullerene electronic states in compounds and at interfaces of primary importance, since the high symmetry of the molecule greatly simplifies the starting point of the analysis. Carbon nanotubes, which combine one macroscopic with two nanoscopic dimensions, are perhaps of even greater practical interest.Angle-dependent electron spectroscopies have been employed in the present work to study these materials, characterizing their structure, bonding, and electronic states. For solid C60, the photoelectron angular distribution has been found to be essentially that of the free molecule, modified by solid state scattering; a similar distribution is found for K3C60.The surface and bulk electronic structure of K3C60 has been identified by angle-dependent core and valence photoelectron spectroscopy (PES) and x-ray emission spectroscopy. An insulating surface layer has been identified for this high-temperature superconductor.Angle-dependent valence PES is used to investigate the electronic states of C60/Al(110). Electron correlations are found to be the origin of the splitting observed in the molecular orbitals, which is quite sensitive to the molecular orientation. The components of the highest occupied molecular orbital are differentiated according to their overlap with the substrate.A rigid shift of valence- and core-levels has been observed even for ionic and covalent C60 compounds, reflecting the efficient static polarizability screening of the molecule. The alignment of multi-walled carbon nanotubes has been investigated by x-ray absorption spectroscopy, using the spectral intensity ratio of π- and -resonances. Core level combined with valence PES shows that the degree of defect structure varies from position to position on the sample. Valence photoelectron spectra of defect-free sample spots closely resembles the total DOS of graphite.
40.	Schiessling, Joachim, et al. (författare) Comment on "Electronic structure of C-60 on Au(887)" [J. Chem. Phys. 125, 144719 (2006)] 2007 Ingår i: Journal of Chemical Physics. - : AIP Publishing. - 0021-9606 .- 1089-7690. ; 127:6 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
41.	Schiessling, Joachim, et al. (författare) Interplay of covalent bonding and correlation effects at molecule-metal contacts 2009 Ingår i: Chemical Physics Letters. - : Elsevier BV. - 0009-2614 .- 1873-4448. ; 478:4-6, s. 191-194 Tidskriftsartikel (refereegranskat)abstract We compare photoelectron spectra (PES) and theoretical densities-of-states of C-60/Al(111), C-60/Al(110) and C-60/Al(100). The splitting observed on all three surfaces is attributed to final state charging. This splitting can also be used to improve estimates of the charging energy U of adsorbed molecules and as a criterion for the existence of strong covalent bonding to the electrode. Au exhibits weak bonding in available data, whereas Ag(100), with measurable charge transfer, appears qualitatively similar to Al.
42.	Schnadt, J., et al. (författare) Beamline-induced Chromium Structure in Carbon K-edge Absorption Spectra 2001 Ingår i: Nucl. Inst. Meth. Phys. Res. B. ; 184, s. 609- Tidskriftsartikel (refereegranskat)
43.	Schnadt, J., et al. (författare) Core-hole screening efficiencies in molecular π systems estimated from a comparison of valence and core excitions Annan publikation (övrigt vetenskapligt/konstnärligt)
44.	Schnadt, J, et al. (författare) Excited-state charge transfer dynamics in systems of aromatic adsorbates on Ti02 studied with resonant core techniques 2003 Ingår i: Journal of Chemical Physics. ; 119:23, s. 12462-12472 Tidskriftsartikel (refereegranskat)
45.	Schnadt, J., et al. (författare) Excited-state charge transfer dynamics in systems of aromatic adsorbates on TiO2 studied with resonant core techniques Annan publikation (övrigt vetenskapligt/konstnärligt)
46.	Schnadt, J., et al. (författare) Structural study of absorption of isonicotinic acid and related molecules on rutile TiO2(110) II.: XPS Annan publikation (övrigt vetenskapligt/konstnärligt)

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