Date: April 29, 2005
Creator: Buda, Corneliu; Kazi, Abul B.; Dinescu, Adriana & Cundari, Thomas R., 1964-
Description: This article discusses stability studies of transition-metal isomers. Several hypotheses to elucidate the linkage isomer preference of the thiocyanate (SCN¯) ion have been offered. For complexes with small coordination numbers (i.e. 1 and 2) and groups 11 (Cu-triad) and 12 (Zn-triad) metals, different levels of theory and a variety of basis sets have been employed to study linkage isomerism. Similar results are obtained for all density functionals tested, pure and hybrid. Overall, good agreement, vis-á-vis experimentally identified linkage isomers, is achieved for ab initio techniques, whereas semiempirical quantum mechanical methods show a bias toward S-ligated isomers. Despite the seeming ease for the a priori prediction of the most stable thiocyanate isomers using acid/base principles, this research highlights the sensitivity of quantitative calculations of transition-metal linkage isomerism to the choice of basis set and electron correlation, particularly with post-Hartree-Fock treatments.
Contributing Partner: UNT College of Arts and Sciences