Rational synthesis of unidimensional mixed valence solids. Structural, spectral, and electrical studies of charge distribution and transport in partially oxidized nickel and palladium bisdiphenylglyoximates

Journal Article · Wed May 23 00:00:00 EDT 1979 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00505a021· OSTI ID:6063542

Cowie, M; Gleizes, A; Grynkewich, G W

A detailed study is presented of solid-state structure, oxidation state, and electron transport in Ni(dpg)/sub 2/I and Pg(dpg)/sub 2/I, dpg = diphenylglyoximato. The crystal structure of Ni(dpg)/sub 2/I has been studied by x-ray diffraction at 23 and -160/sup 0/C. The compound crystallizes in the tetragonal space group D/sub 4h//sup 8/-P4/ncc, with four formula units of Ni(dpg)/sub 2/I in a unit cell having dimensions at -160/sup 0/C of a = 19.774 (8), c = 6.446 (3) A. Full-matrix least-squares refinement of 31 variables gave a final value of the conventional R index (on F) of 0.093 for 353 reflections having F/sub 0//sup 2/ > 3 sigma(F/sub 0//sup 2/). The crystal structure consists of stacked Ni(dpg)/sub 2/ units (staggered by 90/sup 0/) and disordered chains of iodine atoms extending in the c direction. At -160/sup 0/C the Ni--Ni separation is 3.223 (2) A; other important distances are Ni--N = 1.868 (15), N--C = 1.33 (3), N--O = 1.34 (3) A. The Ni(dpg)/sub 2/ moiety is decidedly nonplanar (D/sub 2/ symmetry) with coordinated N atoms displaced 0.12 (2) A above or below the mean molecular plane. Analysis of diffuse x-ray scattering associated with the disordered iodine chains is consistent with I/sub 5//sup -/ being the predominant species. This result is in agreement with resonance Raman spectroscopic studies on Ni(dpg)/sub 2/I and Pd(dpg)/sub 2/I as well as on model compounds. Fundamental polyiodide transitions in the M(dpg)/sub 2/I materials are observed(..nu../sub 0/ = 4880--6471 A)at 161 vs and 107 w cm/sup -1/; weak M(dpg)/sub 2/-centered scattering is also noted. Iodination brings about an increase in conductivity of > 10/sup 8/ (Ni) and > 10/sup 7/ (Pd), which is especially noteworthy since the only major change in crystal structure upon iodination is a ca. 0.27 A decrease in the M(dpg)/sub 2/ stacking distance. Variable-temperature studies show the Ni(dpg)/sub 2/I and Pd(dpg)/sub 2/I conductivities to be thermally activated.

• Research Organization: Northwestern Univ., Evanston, IL
• OSTI ID: 6063542
• Journal Information: J. Am. Chem. Soc.; (United States), Vol. 101:11
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
NICKEL COMPLEXES
STRUCTURAL CHEMICAL ANALYSIS
PALLADIUM COMPLEXES
ACTIVATION ENERGY
BOND ANGLE
CHARGE DISTRIBUTION
CHEMICAL PREPARATION
CHLORINATED AROMATIC HYDROCARBONS
COMPARATIVE EVALUATIONS
CRYSTAL STRUCTURE
ELECTRIC CONDUCTIVITY
ESTERS
EXPERIMENTAL DATA
HETEROCYCLIC COMPOUNDS
INTERATOMIC DISTANCES
ISOLATED VALUES
ISOMER SHIFT
LEAST SQUARE FIT
LOW TEMPERATURE
MEDIUM TEMPERATURE
MOESSBAUER SPECTROMETERS
MOLECULAR STRUCTURE
MONOCRYSTALS
NICKEL IODIDES
ORGANIC NITROGEN COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
ORGANIC SOLVENTS
ORGANOMETALLIC COMPOUNDS
PHOTOELECTRON SPECTROSCOPY
RAMAN SPECTRA
STOICHIOMETRY
TEMPERATURE DEPENDENCE
TETRAGONAL LATTICES
VALENCE
X-RAY DIFFRACTION
AROMATICS
COHERENT SCATTERING
COMPLEXES
CRYSTAL LATTICES
CRYSTALS
DATA
DATA FORMS
DIFFRACTION
DISTANCE
ELECTRICAL PROPERTIES
ELECTRON SPECTROSCOPY
ENERGY
GAMMA SPECTROMETERS
HALIDES
HALOGEN COMPOUNDS
HALOGENATED AROMATIC HYDROCARBONS
INFORMATION
IODIDES
IODINE COMPOUNDS
MAXIMUM-LIKELIHOOD FIT
MEASURING INSTRUMENTS
NICKEL COMPOUNDS
NUMERICAL DATA
NUMERICAL SOLUTION
ORGANIC CHLORINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
PHYSICAL PROPERTIES
SCATTERING
SOLVENTS
SPECTRA
SPECTROMETERS
SPECTROSCOPY
SYNTHESIS
TRANSITION ELEMENT COMPLEXES
TRANSITION ELEMENT COMPOUNDS
400201* - Chemical & Physicochemical Properties
400301 - Organic Chemistry- Chemical & Physicochemical Properties- (-1987)