Effect of pressure on the Raman spectra of solids. 2. Pyridine

Journal Article · Thu Oct 10 04:00:00 EDT 1985 · J. Phys. Chem.; (United States)

DOI:https://doi.org/10.1021/j100267a026· OSTI ID:6177314

Heyns, A M; Venter, M W

Two modifications of pyridine have been identified when the liquid is solidified at 10 kbar in a diamond anvil cell at 300 K. The effect of pressure on the Raman spectra of these modifications is reported. The one modification is crystalline and characterized by narrow and well-defined lattice modes and undergoes a phase transition at 20 kbar, while the other has fewer and much broader lattice vibrations. The Raman spectra of none of these modifications are in agreement with the space group reported for solid pyridine obtained by cooling that liquid at atmospheric pressures. The pressure dependence of the Raman bands of the crystalline phase indicates that it possibly corresponds to the monoclinic phase II in planar, aromatic molecules such as benzene, while the other modification possibly resembles that glassy phase observed in infrared experiments. The internal modes of solid pyridine in all the phases closely resemble those of the liquid. 31 references, 2 figures, 3 tables.

• Research Organization: Univ. of Pretoria, South Africa
• OSTI ID: 6177314
• Journal Information: J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Vol. 89:21; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400301* -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
AZINES
DATA
ENERGY LEVELS
EXCITED STATES
EXPERIMENTAL DATA
HETEROCYCLIC COMPOUNDS
INFORMATION
LASER SPECTROSCOPY
LATTICE VIBRATIONS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHASE STUDIES
PRESSURE DEPENDENCE
PYRIDINE
PYRIDINES
RAMAN SPECTROSCOPY
SPACE GROUPS
SPECTROSCOPY
VERY HIGH PRESSURE
VIBRATIONAL STATES