[Mo2(CN)11]:5- A Detailed Description of Ligand-Field Spectra and Magnetic Properties by First-Principles Calculations

• Published in: The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory Vol. 109; no. 39; pp. 8857 - 8864
• Main Authors: Hendrickx, Marc F. A, Clima, S, Chibotaru, L. F, Ceulemans, A
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 06.10.2005
• ISSN: 1089-5639; 1520-5215
• DOI: 10.1021/jp0509257

An ab initio multiconfigurational approach has been used to calculate the ligand-field spectrum and magnetic properties of the title cyano-bridged dinuclear molybdenum complex. The rather large magnetic coupling parameter J for a single cyano bridge, as derived experimentally for this complex by susceptibility measurements, is confirmed to a high degree of accuracy by our CASPT2 calculations. Its electronic structure is rationalized in terms of spin−spin coupling between the two constituent hexacyano−monomolybdate complexes. An in-depth analysis on the basis of Anderson's kinetic exchange theory provides a qualitative picture of the calculated CASSCF antiferromagnetic ground-state eigenvector in the Mo dimer. Dynamic electron correlations as incorporated into our first-principles calculations by means of the CASPT2 method are essential to obtain quantitative agreement between theory and experiment.