J. C. Dobrowolsk et al.
120
studies [38, 149] and with the support of B3LYP/CoSmo/6-31 + + g** calculations, the bands at 1295 and 1286 cm
−1
of opposite sign were assigned to two methine bending vibrations of the two ring-puckering conformers (Fig. 5.8b) [204].
ROA spectra: Experiment and Calculations the first RoA and Raman spectra of L- and d-proline zwitterionic forms were recorded for light and heavy
water solutions in a wide frequency range and interpreted by means of B3LYP/
CoSmo/6-31 + + g** calculations supported by hF, mP2, and other dFt functional calculations involving both a continuum and an explicit solvent (Fig. 5.9)
[206]. the positions of the water molecules around proline were found by md
simulations. For each of the two proline conformations, 13 complexes with water
(with from 3 to 8 h-bonded waters) were arbitrarily selected for simulation of the
spectra. the 6-31g (water) and 6-31 + + g** (proline) basis sets were used for hF
calculations of the intensity tensors. two distinct but equally populated flexible
Fig. 5.8 (a) VCD and IR spectra of L-proline: α-CD film was prepared from a 200 μL solution
of α-CD (0.050 M) in H 2 O; DL-proline + α-CD film was prepared from a 200 μL solution of DLproline + α-CD (molar ratio: 2:1, 0.050 M for α-CD) in H 2 O; L-proline + α-CD film was prepared
from a 200 μL solution of L-proline + α-CD (molar ratio: 2:1, 0.050 M for α-CD) in H 2 o. (Reproduced from Ref. [38] with kind permission of Society of Applied Spectroscopy) (b) QCL-vCd
spectra of aqueous 3 m solutions of L-proline ( solid blue) and its enantiomer ( dashed red) in a
100 μm CaF 2 cell. Spectra were background-corrected using a 1:1 (3 m) mixture of the two enantiomers. Inset: 3a in water corrected with a pure water background. b) Relative vCd intensities
computed at the B3LYP/CoSmo/6-31 + + g** level for two ring-puckering conformers of the
L-proline zwitterion (1:1, grey and black vertical lines, arb. units). (Reproduced from Ref. [204]
with kind permission of American Chemical Society)
120
studies [38, 149] and with the support of B3LYP/CoSmo/6-31 + + g** calculations, the bands at 1295 and 1286 cm
−1
of opposite sign were assigned to two methine bending vibrations of the two ring-puckering conformers (Fig. 5.8b) [204].
ROA spectra: Experiment and Calculations the first RoA and Raman spectra of L- and d-proline zwitterionic forms were recorded for light and heavy
water solutions in a wide frequency range and interpreted by means of B3LYP/
CoSmo/6-31 + + g** calculations supported by hF, mP2, and other dFt functional calculations involving both a continuum and an explicit solvent (Fig. 5.9)
[206]. the positions of the water molecules around proline were found by md
simulations. For each of the two proline conformations, 13 complexes with water
(with from 3 to 8 h-bonded waters) were arbitrarily selected for simulation of the
spectra. the 6-31g (water) and 6-31 + + g** (proline) basis sets were used for hF
calculations of the intensity tensors. two distinct but equally populated flexible
Fig. 5.8 (a) VCD and IR spectra of L-proline: α-CD film was prepared from a 200 μL solution
of α-CD (0.050 M) in H 2 O; DL-proline + α-CD film was prepared from a 200 μL solution of DLproline + α-CD (molar ratio: 2:1, 0.050 M for α-CD) in H 2 O; L-proline + α-CD film was prepared
from a 200 μL solution of L-proline + α-CD (molar ratio: 2:1, 0.050 M for α-CD) in H 2 o. (Reproduced from Ref. [38] with kind permission of Society of Applied Spectroscopy) (b) QCL-vCd
spectra of aqueous 3 m solutions of L-proline ( solid blue) and its enantiomer ( dashed red) in a
100 μm CaF 2 cell. Spectra were background-corrected using a 1:1 (3 m) mixture of the two enantiomers. Inset: 3a in water corrected with a pure water background. b) Relative vCd intensities
computed at the B3LYP/CoSmo/6-31 + + g** level for two ring-puckering conformers of the
L-proline zwitterion (1:1, grey and black vertical lines, arb. units). (Reproduced from Ref. [204]
with kind permission of American Chemical Society)