title: Large Ligand Folding Distortion in an Oxomolybdenum Donor-Acceptor Complex.
abstract: Interligand charge transfer is examined in the novel metallo-dithiolene complex MoO(SPh)2((i)Pr2Dt(0)) (where (i)Pr2Dt(0) = N,N'-isopropyl-piperazine-2,3-dithione). The title complex displays a remarkable 70° "envelope"-type fold of the five-membered dithiolene ring, which is bent upward toward the terminal oxo ligand. A combination of electronic absorption and resonance Raman spectroscopies have been used to probe the basic electronic structure responsible for the large fold-angle distortion. The intense charge transfer transition observed at ∼18 000 cm(-1) is assigned as a thiolate → dithione ligand-to-ligand charge transfer (LL'CT) transition that also possesses Mo(IV) → dithione charge transfer character. Strong orbital mixing between occupied and virtual orbitals with Mo(x(2)-y(2)) orbital character is derived from a strong pseudo Jahn-Teller effect, which drives the large fold-angle distortion to yield a double-well potential in the electronic ground state.
authors.affiliation: Department of Chemistry and Chemical Biology, The University of New Mexico , MSC03 2060, 1 University of New Mexico, Albuquerque, New Mexico 87131-0001, United States .
authors.forename: Jing
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department of Chemistry and Biochemistry, Duquesne University , Pittsburgh, Pennsylvania 15282, United States.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Mogesa
authors.affiliation: Department of Chemistry and Biochemistry, Duquesne University , Pittsburgh, Pennsylvania 15282, United States.
authors.forename: Partha
authors.initials: P
authors.lastname: Basu
authors.affiliation: Department of Chemistry and Chemical Biology, The University of New Mexico , MSC03 2060, 1 University of New Mexico, Albuquerque, New Mexico 87131-0001, United States .
authors.forename: Martin L
authors.initials: ML
authors.lastname: Kirk
mesh_terms: D008024:Ligands; D008968:Molecular Conformation; D008982:Molybdenum / Q000737:chemistry*
chemical_list: D008024:Ligands; D008982:Molybdenum