Investigating the anharmonicity of lattice vibrations in water-containing molecular crystals through the terahertz spectroscopy of L-serine monohydrate.
The influence of cocrystallized H(2)O molecules on the terahertz (THz) spectra and corresponding computational treatment of hydrated molecular crystals was investigated in the study of protonated and deuterium-substituted l-serine.H(2)O. The THz spectra of both solids have been measured in the range of 10 to 90 cm(-1), with simulations of the crystalline structure and THz vibrational modes performed using solid-state density functional theory. Significant and systematic overestimations of the predicted vibrational frequencies were observed in all calculations. Evidence provided by the comparison of the experimental and calculated vibrational frequencies for both the protonated and deuterated l-serine.H(2)O solids indicates the presence of significant anharmonicity in the observed lattice vibrations. The results suggest that vibrational anharmonicity may play a much larger role in the interpretation of the THz spectra of hydrates in contrast to their corresponding anhydrous forms.
King
Matthew D
MD
Department of Chemistry, Syracuse University, 1-014 Center for Science and Technology, Syracuse, New York 13244-4100, USA.
Buchanan
William D
WD
Korter
Timothy M
TM
D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D008958:Models, Molecular; D056004:Molecular Dynamics Simulation; D015394:Molecular Structure; D012694:Serine / Q000031:analogs & derivatives / Q000737:chemistry*; D055068:Terahertz Spectroscopy / Q000379:methods*; D014732:Vibration; D014867:Water / Q000737:chemistry*
D014867:Water; D012694:Serine