Structural studies of precursor and partially oxidized conducting complexes. XIII. A neutron diffraction and x-ray diffuse scattering study of the dimerized platinum chain in rubidium tetracyanoplatinate chloride (2:1:0. 3) trihydrate, Rb/sub 2/(Pt(CN)/sub 4/)Cl/sub 0/ /sub 3/. 3. 0H/sub 2/O

Journal Article · Sat Apr 01 04:00:00 EST 1978 · Inorg. Chem.; (United States)

DOI:https://doi.org/10.1021/ic50182a009· OSTI ID:6683861

Williams, J M; Johnson, P L; Schultz, A J; Coffey, C C

The crystal structure and molecular formula of the one-dimensional conductor Rb/sub 2/(Pt(CN)/sub 4/)Cl/sub 0/./sub 30/ . 3.0H/sub 2/O, RbCP(Cl), have been fully characterized using single-crystal neutron diffraction, x-ray diffuse scattering data, and thermogravimetric analysis. RbCP(Cl) is isostructural with KCP(Cl) and KCP(Br) except that only one halide site can be identified. From thermogravimetric analyses RbCP(Cl) is a 3.0 hydrate as is KCP(Br). RbCP(Cl) crystallizes in the tetragonal space group P4mm, with unit cell dimensions a = 10.142 (6) A, c = 5.801 (4) A, V/sub c/ = 596.7 A/sup 3/, and Z = 2. Using x-ray diffuse scattering techniques we have established the Pt oxidation as +2.31 (2) from which the molecular formula Rb/sub 2/(Pt(CN)/sub 4/)Cl/sub 0.31(2)/ . 3.0H/sub 2/O is obtained. The structure consists of nearly planar Pt(CN)/sub 4/ moieties stacked along the c axis forming a perfectly linear Pt-Pt chain. The crystal asymmetric unit contains two independent Pt(CN)/sub 4//sup 1/./sup 7 -/ groups, two H/sub 2/O sites, one Rb/sup +/ site, and one Cl/sup -/ site. The asymmetric ordering of the Rb/sup +/ ion and the H/sub 2/O molecules constitutes the main source of crystal asymmetry. The two-independent Pt-Pt chain distances are definitely unequal (2.877 (8) and 2.924 (8) A) with the average intrachain separation (2.90 A) being slightly longer than in KCP(Br) (2.88 A) and KCP(Cl) (2.87 A). The replacement of K/sup +/ by Rb/sup +/ results in lattice expansion along c, which produces larger Pt-Pt intrachain separations. Thus the unequal and slightly longer Pt-Pt separations in RbCP(Cl), apparently result in increased electron localization along the Pt-atom chain and a concomitant decrease in the electrical conductivity. 10 figures, 3 tables.

• Research Organization: Argonne National Lab., IL
• OSTI ID: 6683861
• Journal Information: Inorg. Chem.; (United States), Journal Name: Inorg. Chem.; (United States) Vol. 17:4; ISSN INOCA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ALKALI METAL COMPLEXES
ASYMMETRY
BOND LENGTHS
CHEMICAL ANALYSIS
CHEMICAL PREPARATION
CHLORINE COMPLEXES
COHERENT SCATTERING
COMPLEXES
CRYSTAL STRUCTURE
CYANIDES
DIFFRACTION
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
FOURIER ANALYSIS
GRAVIMETRIC ANALYSIS
HYDRATES
LEAST SQUARE FIT
MAXIMUM-LIKELIHOOD FIT
MOLECULAR STRUCTURE
NEUTRON DIFFRACTION
NUMERICAL SOLUTION
PHYSICAL PROPERTIES
PLATINUM COMPLEXES
PRECURSOR
QUANTITATIVE CHEMICAL ANALYSIS
RUBIDIUM COMPLEXES
SCATTERING
STRUCTURAL CHEMICAL ANALYSIS
SYNTHESIS
THERMAL ANALYSIS
THERMAL GRAVIMETRIC ANALYSIS
TRANSITION ELEMENT COMPLEXES
X-RAY DIFFRACTION