[TDHF study of electronic absorption spectrum of (mu-L1) (mu-L2)-decacarbonyl triosmium].
Ab initio method was used to optimize the molecular geometry for a series of clusters (mu-L1) (mu-L2)- decacarbonyltri-osmium [L1, L2 = H, Cl, Br, I] at HF/CEP-4G level. The related chemical properties of clusters, in particular, the regularities of the bridge halogen effects on spectroscopic properties and bonding properties were discussed. The calculation results of the frontier molecular orbital showed that M-M bonds were mainly composed of s and d atomic orbitals. From Cl to I, with the atom number of bridge ligand increasing, HOMO and NHOMO orbitals on the Os3(CO)10 (mu-L)2 clusters and HOMO on the Os3 (CO)10 (mu-H) (mu-L) clusters become higher, while deltaepsilonL-H and deltaepsilon-NH energies become lower, so the authors predicted that the electronic absorption bands of clusters are shifted to infrared region. Excited states of clusters calculated with TDHF show that the transition of cluster Os3(CO)10 (mu-H)2 (I) is mainly 7 --> sigma* and sigma --> sigma*, while the electronic absorption of other clusters Os3 (CO)10 (mu-H) (mu-L) [L = Cl, Br, I] and Os3(CO)10 (mu-L)2 [-L = Cl, Br] is mainly from sigma --> sigma* transition. From Cl to I, with the atom number of bridge ligand increasing, the electronic absorption band of cluster is shifted to infrared region, and also the absorption becomes weaker.
Zeng
Rong-Ying
RY
Department of Chemistry Materials Science, Hengyang Normal University, Hengyang 421008, China. zengrongying2003@yahoo.com.cn
Tang
Wen-Qing
WQ
Kuang
Dai-Zhi
DZ
Chen
Zhi-Min
ZM
Lu
Song
S
Yi
Xiang-Hui
XH