Pressure and concentration dependent formation of oligomers of tetrakis-( p-methylphenylisocyanide)rhodium(I)

• Published in: Inorganica Chimica Acta Vol. 216; no. 1; pp. 245 - 247
• Main Authors: Trümbach, Dietrich, Kritzenberger, Jürgen, Yersin, Hartmut
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.02.1994; Elsevier Science
• Subjects: Chemistry; Coordination compounds; Exact sciences and technology; Inorganic chemistry and origins of life; Isocyanide complexes; Oligomer formation; Preparations and properties; Rhodium complexes; Spectroscopic studies; Rhodium complexes; Oligomer formation; Spectroscopic studies; Isocyanide complexes; Cationic complex; Organic ligand; Tetranuclear complex; Transition metal Complexes; Pressure; Absorption spectrum; Chemical equilibrium; Medium effect; Rhodium I Complexes; Content; Platinoid Complexes; Isocyanide; Univalent metal Complexes
• ISSN: 0020-1693; 1873-3255
• DOI: 10.1016/0020-1693(93)03725-P

The optical absorption of [Rh(tol) 4]PF 6 (tol: p-methylphenyl- isocyanide) dissolved in acetonitrile has been measured as function of concentration (10 −4 ⩽ c 0⩽1.5×10 −2 mol/l) and of applied pressure (0.1⩽ p⩽400 MPa) at room temperature. Analysis of the spectra indicates the formation of oligomers [Rh(tol) 4] n n+ , n=2,3, with increase of both the concentration and the pressure, respectively. Application of pressure increases the dimer-monomer equilibrium constant and yields a blue shift (≈0.3 cm −1/MPa) of the monomer absorption but a red shift (≈−0.6 cm −1/MPa) of the dimer absorption.