Electronic structure and properties of MCO and M5CO carbonyls (M = Fe, Ni, Cu) by density functional methods

✍ Scribed by Ramon M. Sosa; Patricia Gardiol

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 1013 KB
• Volume: 60
• Category: Article
• ISSN: 0020-7608
• DOI: 10.1002/(sici)1097-461x(1996)60:7<1429::aid-qua25>3.0.co;2-y

✦ Synopsis

Density functional theory (DFT) calculations of the electronic structure and properties of Fe, Ni, and Cu carbonyls with one and five transition-element atoms are reported, due to their importance in heterogeneous catalysis (especially in Fischer-Tropsch synthesis). The local density approximation (LDA) with the Vosko-Wilk-Nussain (VWN) correlation functional as well as the generalized gradient approximation (GGA) using Becke's 1988 exchange functional and Perdew's 1986 correlation functional (BP method) were applied to the study of the clusters using a triple-zeta plus polarization (TZP) basis set. Triplet and quintuplet states for FeCO, singlet and triplet for NiCO, and doublet for CuCO were considered, and optimization of energy at the LDA/BP level for these cases was done. Dissociation energies in M and CO fragments, frequencies, and population analysis were performed. Geometry optimization of the distance between the C atom and the clusters M, (with geometries taken from the crystals) were carried out and the dissociation energy in fragments M, and CO as well as population analysis at the optimized geometries were also done. Comparison between our results and some others published using ab initio and density functional methods were performed. Sons, Inc.