Phosphinidene Transition Metal Complexes: A Combined Ab Initio MO-DFT Study of Cr(CO)5–PR

✍ Scribed by Steven Creve; Kristine Pierloot; Minh Tho Nguyen; Luc G. Vanquickenborne

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 396 KB
• Volume: 1999
• Category: Article
• ISSN: 1434-1948
• DOI: 10.1002/(sici)1099-0682(199901)1999:1<107::aid-ejic107>3.0.co;2-4

✦ Synopsis

Ab initio MO and DFT calculations have been performed on and triplet states, all complexes exhibit a staggered conformation. CASSCF/CASPT2 calculations performed with phosphinidene complexes of the type Cr(CO) 5 -PR, with R = H, CH 3 , SiH 3 , NH 2 , PH 2 , OH, and SH. The formation of the the ANO basis sets indicate a closed-shell singlet ground state along the whole series. The binding energy between Cr-P bond essentially arises from a ligand-to-metal charge transfer. While a significant π backdonation is also observed Cr(CO) 5 and PR ranges from 216 kJ/mol for Cr(CO) 5 -PNH 2 to 127 kJ/mol for Cr(CO) 5 -PSiH 3 (B3LYP values). In general, for the Cr(CO) 5 -PH, Cr(CO) 5 -PCH 3 , and Cr(CO) 5 -PSiH 3 complexes, this is less the case for Cr(CO) 5 -POH, Cr(CO) 5 -the B3LYP-DFT scheme yields reasonable qualitative and quantitative results when compared with CASPT2(12/12). PSH, and Cr(CO) 5 -PNH 2 , and the backbonding almost disappears for Cr(CO) 5 -PPH 2 . In both the lowest lying singlet throughout, based on parameters chosen from experimental [a]