Anisotropy of intermolecular interactions, band electronic structure, and electrical properties of. beta. -(ET)/sub 2/AuCl/sub 2/. [. beta. -bis(ethylenedithio)tetrathiafulvalene gold chloride]
A new organic salt, ..beta..-(ET)/sub 2/AuCl/sub 2/, was synthesized, and its structure and physical properties were determined. Here ET refers to bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF or ET). ..beta..-(ET)/sub 2/AuCl/sub 2/ is isostructural with ..beta..-(ET)/sub 2/ICl/sub 2/ and contains the shortest anion, AuCl/sub 2//sup -/, among the ..beta..-(ET)/sub 2/X salts with linear anions, X/sup -/, known so far. Crystal data for ..beta..-(ET)/sub 2/AuCl/sub 2/ are as follows: triclinic, P anti 1, 298 K/120 K, a = 6.651 (1)/6.627 (2) A, b = 9.761 (2)/9.595 (3) A, c = 12.734 (3)/12.662 (4) A, ..cap alpha.. = 86.12 (2)/85.15 (2)/sup 0/, ..beta.. = 100.70 (2)/101.40 (2)/sup 0/, ..gamma.. = 99.41 (2)/98.24 (2)/sup 0/, and V/sub c/ = 800.7 (4)/779.8 (5) A/sup 3/. The electrical conductivities of type I ..beta..-(ET)/sub 2/X salts (i.e., those with short anions X/sup -/ = AuCl/sub 2//sup -/, ICl/sub 2//sup -/) measured by the four-probe technique show that they are semiconductors with thermal activation energy of 0.10 eV. The valence band (i.e., the highest occupied band) of ..beta..-(ET)/sub 2/AuCl/sub 2/, which is half-filled, is calculated to be one-dimensional in character as in the case of ..beta..-(ET)/sub 2/ICl/sub 2/. ESR data of ..beta..-(ET)/sub 2/AuCl/sub 2/ reveal the presence of a phase transition at approx. 33 K, which is somewhat higher than the corresponding temperature (22 K) of ..beta..-(ET)/sub 2/ICl/sub 2/. The ET molecule pairs of type I ..beta..-(ET)/sub 2/X salts are significantly more dimerized than those of type II ..beta..-(ET)/sub 2/X salts (i.e., those with long anions X/sup -/ = IBr/sub 2//sup -/, AuI/sub 2//sup -/, I/sub 3//sup -/).
- Research Organization:
- Argonne National Lab., IL
- DOE Contract Number:
- W-31-109-ENG-38; FG05-86ER45259
- OSTI ID:
- 6510055
- Journal Information:
- J. Am. Chem. Soc.; (United States), Vol. 109:7
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
GOLD CHLORIDES
CHEMICAL PREPARATION
CRYSTAL STRUCTURE
ELECTRICAL PROPERTIES
ELECTRONIC STRUCTURE
ORGANIC SULFUR COMPOUNDS
ELECTRON SPIN RESONANCE
EXPERIMENTAL DATA
LATTICE PARAMETERS
X-RAY DIFFRACTION
CHLORIDES
CHLORINE COMPOUNDS
COHERENT SCATTERING
DATA
DIFFRACTION
GOLD COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
INFORMATION
MAGNETIC RESONANCE
NUMERICAL DATA
ORGANIC COMPOUNDS
PHYSICAL PROPERTIES
RESONANCE
SCATTERING
SYNTHESIS
TRANSITION ELEMENT COMPOUNDS
400201* - Chemical & Physicochemical Properties