| 1. |
- Hegelund, F, et al.
(författare)
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The infrared spectrum of isothiazole in the range 600-1500 cm(-1), including a high-resolution study of the v(11)(A ') band at 818cm(-1) and the v(16)(A '') band at 727cm(-1), together with ab initio studies of the full spectrum
- 2004
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Ingår i: Molecular Physics. - : Informa UK Limited. - 1362-3028 .- 0026-8976. ; 102:14-15, s. 1583-1595
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Tidskriftsartikel (refereegranskat)abstract
- The gas-phase high-resolution infrared spectrum of isothiazole in the range 600-1500 cm(-1) has been recorded, and revised band centres obtained for a number of vibrations. An analysis of the nu(11)(A') band at 818 cm(-1) and the nu(16)(A") band at 727cm(-1) has been performed, using the Watson Hamiltonian, A-reduction, IIIr representation. These were combined with previous microwave spectral data to provide combined analyses for rotational constants and quartic centrifugal distortion constants Delta(J), Delta(JK), Delta(K), delta(J) and delta(K). These extend the knowledge derived from previous microwave and IR spectral studies. The equilibrium structures and the derived harmonic frequencies were calculated by ab initio methods, using a variety of basis sets with MP2, MP4 and CCSD(T) methods, and a comparison of these with experimental data is discussed. At a pragmatic level, the closest correlation of the rotational constants with experiment is not obtained with the most sophisticated methodology. Similarly, the vibration frequencies and intensities also vary strongly with the procedure. In particular, we found that the cc-pVTZ + MP2 results probably provide the best numerical comparison with experimental IR data for this molecule.
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| 2. |
- Lakens, Daniel, et al.
(författare)
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Justify your alpha
- 2018
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Ingår i: Nature Human Behaviour. - : Nature Publishing Group. - 2397-3374. ; 2:3, s. 168-171
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Tidskriftsartikel (refereegranskat)abstract
- In response to recommendations to redefine statistical significance to P ≤ 0.005, we propose that researchers should transparently report and justify all choices they make when designing a study, including the alpha level.
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| 3. |
- Palmer, MH, et al.
(författare)
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The infrared spectrum of isoxazole in the range 600-1400 cm(-1), including a high-resolution study of the v(7)(A ') band at 1370.9cm(-1) and the v(16)(A '') band at 764.9cm(-1), together with ab initio studies of the full spectrum
- 2004
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Ingår i: Molecular Physics. - : Informa UK Limited. - 1362-3028 .- 0026-8976. ; 102:14-15, s. 1569-1581
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Tidskriftsartikel (refereegranskat)abstract
- The high resolution infrared gas phase spectrum of isoxazole in the range 600-1400 cm(-1) has been recorded and more precise centres obtained for a number of bands; analyses of the nu(7)(A') band at 1370.9 cm(-1) and the nu(16)(A") band at 764.9 cm(-1) have been performed. Use of the Watson Hamiltonian, A-reduction, IIIr-representation and simultaneous analysis of the present IR and previous microwave data, has led to rotation constants and quartic centrifugal distortion constants Delta(J), Delta(JK), Delta(K), delta(J) and delta(K) for the ground state and for the nu(16) vibrationally excited states. The equilibrium structures and the derived harmonic frequencies have been calculated by ab initio methods using triple zeta + polarization (TZVP) and cc-pVTZ basis sets, with MP2, MP4 and CCSD(T) methods. At each methodology, for closest numerical agreement between the calculated and observed rotation constants, the optimum basis set seems to be TZVP rather than cc-pVTZ basis sets. However, the order of the highest A" and lowest A' symmetry vibrations is only resolved by the cc-pVTZ basis set with the MP4 methodology, which does generate the experimental sequence (nu(14)>nu(13)). The CCSD(T) methodology does not lead to significant difference over either MP2 or MP4 with the TZVP basis set.
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