Pressure-tuning spectroscopy of charge-transfer salts. X-ray crystallography and comparative studies in solution and in the solid state

Journal Article · Thu Nov 01 00:00:00 EST 1990 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100385a024· OSTI ID:6286894

Bockman, T M; Kochi, J K ^[1]; Chang, H R; Drickamer, H G ^[2]

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1. Univ. of Houston, TX (USA)
2. Univ. of Illinois, Urbana (USA)

The highly colored pyridinium (P{sup +}) and cobaltocenium (C{sup +}) iodides are charge-transfer salts by virtue of the new electronic absorption bands that follow Mulliken theory. X-ray crystallography establishes the relevant interionic separation and steric orientation of the cation/anion pairs P{sup +}I{sup {minus}} and C{sup +}I{sup {minus}} constrained for optimum charge-transfer interaction in the crystal lattice. Spectral comparisons of the charge-transfer (CT) transitions by absorption (solution) and by diffuse reflectance (solid-state) measurements reveals the commonality of contact ion pairs (CIP) in aprotic nonpolar solvents (dichloromethane) with those extant in crystalline charge-transfer salts. As such, the compression of the charge-transfer salts P{sup +}I{sup {minus}} in the solid state by the application of pressures up to 140 kbar leads to unusual red shifts of the CT bands indicative of the dominance of destabilizing charge-transfer interactions.

• DOE Contract Number: AC02-76ER01198
• OSTI ID: 6286894
• Journal Information: Journal of Physical Chemistry; (USA), Vol. 94:22; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
COBALT IODIDES
ABSORPTION SPECTROSCOPY
CRYSTAL STRUCTURE
PYRIDINIUM COMPOUNDS
CHARGE TRANSPORT
CRYSTALLOGRAPHY
ELECTRICAL PROPERTIES
EXPERIMENTAL DATA
LATTICE PARAMETERS
AMINES
AMMONIUM COMPOUNDS
AZINES
COBALT COMPOUNDS
DATA
HALIDES
HALOGEN COMPOUNDS
HETEROCYCLIC COMPOUNDS
INFORMATION
IODIDES
IODINE COMPOUNDS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHYSICAL PROPERTIES
PYRIDINES
QUATERNARY COMPOUNDS
SPECTROSCOPY
TRANSITION ELEMENT COMPOUNDS
400201* - Chemical & Physicochemical Properties