Single-crystal X-ray and neutron diffraction investigations of the temperature dependence of the structure of the Tc = 10 K organic superconductor. kappa. -(ET) sub 2 Cu(NCS) sub 2. [where ET or BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene, C sub 10 H sub 8 S sub 8]
- Argonne National Lab., IL (United States)
- North Carolina State Univ., Raleigh (United States)
The crystal structure of {kappa}-(ET){sub 2}Cu(NCS){sub 2} (ET or BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene, C{sub 10}H{sub 8}S{sub 8}) has been examined by single-crystal neutron and X-ray diffraction at temperatures between 298 and 15 K. Comparison of the low temperature ordered structures determined by use of X-ray and neutron diffraction with the previously reported crystallographically disordered room temperature X-ray structure indicates the avoidance of close H{center dot}{center dot}{center dot}H contacts as the reason for the conformational disorder of the terminal ethylene groups of the ET molecules at high temperatures. The space group is monoclinic noncentrosymmetric P2{sub 1}, Z = 2. Unit cell parameters at 118 K are a = 16.359(4), b = 8.418(2), c = 12.855(3) {angstrom}, {beta} = 111.21(2){degree}, and V = 1650.3(7) {angstrom}{sup 3}; at 15 K, a = 16.373(5), b = 8.375(3), c = 12.775(6) {angstrom}, {beta} = 111.45(4){degree}, and V = 1630(1) {angstrom}{sup 3}. The interlayer spacing a {center dot} sin {beta} remains constant upon cooling from 298 to 15 K even though the a axis increases slightly in length.
- DOE Contract Number:
- W-31109-ENG-38; FG05-86ER45259
- OSTI ID:
- 7018082
- Journal Information:
- Journal of Solid State Chemistry; (United States), Vol. 94:2; ISSN 0022-4596
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ORGANIC SUPERCONDUCTORS
NEUTRON DIFFRACTION
X-RAY DIFFRACTION
BOND LENGTHS
BRAGG CURVE
CONFORMATIONAL CHANGES
COPPER COMPLEXES
CRITICAL TEMPERATURE
CRYSTAL STRUCTURE
DIMERS
GONIOMETERS
LAUE METHOD
MOLECULAR STRUCTURE
MONOCLINIC LATTICES
NEUTRON DIFFRACTOMETERS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
PRESSURE DEPENDENCE
STRUCTURAL CHEMICAL ANALYSIS
TEMPERATURE DEPENDENCE
COHERENT SCATTERING
COMPLEXES
CRYSTAL LATTICES
DIAGRAMS
DIFFRACTION
DIFFRACTION METHODS
DIFFRACTOMETERS
DIMENSIONS
LENGTH
MEASURING INSTRUMENTS
SCATTERING
SUPERCONDUCTORS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPLEXES
TRANSITION TEMPERATURE
360602* - Other Materials- Structure & Phase Studies