Intercalation of stable organic radicals into layered inorganic host matrices: Preparation and structural characterization of Cd{sub 1-x}PS{sub 3}(metaMPYNN){sub 2x}

Journal Article · Tue Dec 15 00:00:00 EST 2009 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2009.09.030· OSTI ID:21372429

Hemme, Wilhelm L ^[1]; Fujita, Wataru; Awaga, Kunio ^[2]; Eckert, Hellmut ^[1]

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1. Institut fuer Physikalische Chemie, Westfaelische Wilhelms-Universitaet, Corrensstr. 30, 48149 Muenster (Germany)
2. Research Center for Materials Sciences and Department of Chemistry, Nagoya University Furo-cho, Chikusa, Nagoya 464-8602 (Japan)

The radical cation 2-(3-N-methylpyridinium)-4,4,5,5-tetramethyl-4, 5-dihydro-1H-imidazol-1-oxyl-3-N-oxide (abbreviated as m-MPYNN) is successfully intercalated into the layered host structure CdPS{sub 3}. The reaction proceeds via an ion exchange reaction from methanol solutions containing the radical iodide salt, leading to materials described by the compositional formula Cd{sub 1-x}PS{sub 3}(metaMPYNN){sub 2x}. Detailed characterization of the intercalates by chemical analysis, X-ray powder diffraction, EPR, and NMR spectroscopy indicate that the maximum uptake corresponds to x=0.20; attempts to produce higher intercalated materials result in the formation of a side product with inferred composition CdI{sub 4}(metaMPYNN){sub 2}. Magnetic susceptibility measurements indicate CURIE-like behavior for x=0.13, while at higher intercalation levels antiferromagnetic coupling is observed. The magnetic properties may be linked to the orientation of the radical ions relative to the host layers, which is also found to depend on x. While for the low-intercalated regime (x=0.13) both a transversal intercalation with the N-O director pointing towards the layers, and a longitudinal orientation, with the long axis of the molecule pointing towards the layers are found, at larger x-values only the longitudinal orientation is present. {sup 1}H NMR chemical shifts indicate that the orientation greatly influences the molecular spin density distributions. Modern single and double resonance solid state NMR techniques have been introduced successfully to study the structural modifications of the host lattice and the details of the intermolecular guest/host interactions. Specifically the internuclear distance correlations extracted from selectively measured {sup 1}H-{sup 31}P magnetic dipole-dipole couplings via {sup 31}P/{sup 1}H rotational echo double resonance (REDOR) experiments allow important conclusions regarding the orientation of the guest species relative to the inorganic layers. - Graphical abstract: The orientation of a nitroxide radical relative to the CdPS{sub 3} layers in the corresponding intercalation compound is inferred from x-ray diffraction and solid state NMR spectroscopy.

• OSTI ID: 21372429
• Journal Information: Journal of Solid State Chemistry, Vol. 182, Issue 12; Other Information: DOI: 10.1016/j.jssc.2009.09.030; PII: S0022-4596(09)00465-4; Copyright (c) 2009 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ANTIFERROMAGNETISM
CADMIUM COMPOUNDS
CLATHRATES
ELECTRON SPIN RESONANCE
IODIDES
ION EXCHANGE
LAYERS
MAGNETIC DIPOLES
MAGNETIC SUSCEPTIBILITY
NUCLEAR MAGNETIC RESONANCE
ORIENTATION
PHOSPHORUS COMPOUNDS
SULFUR COMPOUNDS
X-RAY DIFFRACTION
COHERENT SCATTERING
DIFFRACTION
DIPOLES
HALIDES
HALOGEN COMPOUNDS
IODINE COMPOUNDS
MAGNETIC PROPERTIES
MAGNETIC RESONANCE
MAGNETISM
MULTIPOLES
PHYSICAL PROPERTIES
RESONANCE
SCATTERING