| 1. |
- Björnehohn, E., et al.
(författare)
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Water at Interfaces
- 2016
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Ingår i: Chemical Reviews. - : American Chemical Society (ACS). - 0009-2665 .- 1520-6890. ; 116:13, s. 7698-7726
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Forskningsöversikt (refereegranskat)abstract
- The interfaces of neat water and aqueous solutions play a prominent role in many technological processes and in the environment. Examples of aqueous interfaces are ultrathin water films that cover most hydrophilic surfaces under ambient relative humidities, the liquid/solid interface which drives many electrochemical reactions, and the liquid/vapor interface, which governs the uptake and release of trace gases by the oceans and cloud droplets. In this article we review some of the recent experimental and theoretical advances in our knowledge of the properties of aqueous interfaces and discuss open questions and gaps in our understanding.
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| 2. |
- Liriano, Melissa L., et al.
(författare)
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Water-Ice Analogues of Polycyclic Aromatic Hydrocarbons: Water Nanoclusters on Cu(111)
- 2017
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Ingår i: Journal of the American Chemical Society. - : American Chemical Society (ACS). - 1520-5126 .- 0002-7863. ; 139:18, s. 6403-6410
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Tidskriftsartikel (refereegranskat)abstract
- Water has an incredible ability to form a rich variety of structures, with 16 bulk ice phases identified, for example, as well as numerous distinct structures for water at interfaces or under confinement. Many of these structures are built from hexagonal motifs of water molecules, and indeed, for water on metal surfaces, individual hexamers of just six water molecules have been observed. Here, we report the results of low-temperature scanning tunneling microscopy experiments and density functional theory calculations which reveal a host of new structures for water-ice nanoclusters when adsorbed on an atomically flat Cu surface. The H-bonding networks within the nanoclusters resemble the resonance structures of polycyclic aromatic hydrocarbons, and water-ice analogues of inene, naphthalene, phenalene, anthracene, phenanthrene, and triphenylene have been observed. The specific structures identified and the H-bonding patterns within them reveal new insight about water on metals that allows us to refine the so-called "2D ice rules", which have so far proved useful in understanding water-ice structures at solid surfaces.
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| 3. |
- Schnadt, Joachim, et al.
(författare)
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Experimental and theoretical study of oxygen adsorption structures on Ag(111)
- 2009
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Ingår i: Physical Review B (Condensed Matter and Materials Physics). - 1098-0121. ; 80:7
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Tidskriftsartikel (refereegranskat)abstract
- The oxidized Ag(111) surface has been studied by a combination of experimental and theoretical methods, scanning tunneling microscopy, x-ray photoelectron spectroscopy, and density functional theory. A large variety of different surface structures is found, depending on the detailed preparation conditions. The observed structures fall into four classes: (a) individually chemisorbed atomic oxygen atoms, (b) three different oxygen overlayer structures, including the well-known p(4x4) phase, formed from the same Ag-6 and Ag-10 building blocks, (c) a c(4x8) structure not previously observed, and (d) at higher oxygen coverages structures characterized by stripes along the high-symmetry directions of the Ag(111) substrate. Our analysis provides a detailed explanation of the atomic-scale geometry of the Ag-6/Ag-10 building block structures and the c(4x8) and stripe structures are discussed in detail. The observation of many different and co-existing structures implies that the O/Ag(111) system is characterized by a significantly larger degree of complexity than previously anticipated, and this will impact our understanding of oxidation catalysis processes on Ag catalysts.
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| 4. |
- Schnadt, Joachim, et al.
(författare)
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Revisiting the structure of the p(4x4) surface oxide on Ag(111)
- 2006
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Ingår i: Physical Review Letters. - 1079-7114. ; 96
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Tidskriftsartikel (refereegranskat)abstract
- Scanning tunneling microscopy (STM) and density-functional theory are used to reexamine the structure of the renowned p(4×4)-O/Ag(111) surface oxide. The accepted structural model [C. I. Carlisle et al., Phys. Rev. Lett. 84, 3899 (2000)] is incompatible with the enhanced resolution of the current STM measurements. An "Ag6 model" is proposed that is more stable than its predecessor and accounts for the coexistence of the p(4×4) and a novel c(3×5sqrt(3))rect phase. This coexistence is an indication of the dynamic complexity of the system that until now has not been appreciated.
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