Photoelectron Spectroscopy of the Bis(dithiolene) Anions [M(mnt)2]n- (M = Fe - Zn; n = 1, 2): Changes in Electronic Structure with Variation of Metal Center and with Oxidation

Journal Article · Mon Jul 24 04:00:00 EDT 2006 · Inorganic Chemistry

DOI:https://doi.org/10.1021/ic060255z· OSTI ID:993381

Waters, Tom; Wang, Xue B; Woo, Hin-koon; Wang, Lai S

A detailed understanding of the electronic structures of transition metal bis(dithiolene) centers is important in the context of their interesting redox, magnetic and optical properties. The electronic structures of the series [M(mnt)2]n- (M = Fe - Zn; mnt = 1,2-S2C2(CN)2; n = 1, 2) were examined by a combination of photodetachment photoelectron spectroscopy and density functional theory calculations, providing insights into changes in electronic structure with variation of the metal center and with oxidation. Significant changes were observed for the dianions [M(mnt)2]2- due to stabilization of the metal 3d levels from Fe to Zn and the transition from square-planar to tetrahedral coordination about the metal center (Fe-Ni, D2h →Cu D2 →Zn, D2d). Changes with oxidation from [M(mnt)2]2- to [M(mnt)2]1- were largely dependent on the nature of the redox-active orbital in the couple [M(mnt)2]2-/1-. In particular, the first detachment feature for [Fe(mnt)2]2- originated from a metal-based orbital (FeII →FeIII) while that for [Fe(mnt)2]1- originated from a ligand-based orbital, a consequence of stabilization of Fe 3d levels in the latter. In contrast, the first detachment feature for both of [Ni(mnt)2]2- and [Ni(mnt)2]1- originated from the same ligand-based orbital in both cases, a result of occupied Ni 3d levels being stabilized relative those of Fe 3d and occurring below the highest energy occupied ligand-based orbital for both of [Ni(mnt)2]2- and [Ni(mnt)2]1-. The combined data illustrate the subtle interplay between metal- and ligand-based redox chemistry in these species, and demonstrate changes in their electronic structures with variation of metal center, with oxidation, and with coordination geometry.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 993381
• Report Number(s): PNNL-SA-50518; 25392; KP1704020
• Journal Information: Inorganic Chemistry, Journal Name: Inorganic Chemistry Journal Issue: 15 Vol. 45; ISSN 0020-1669; ISSN INOCAJ
• Publisher: American Chemical Society (ACS)
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ANIONS
CHEMISTRY
ELECTRONIC STRUCTURE
Environmental Molecular Sciences Laboratory
FUNCTIONALS
GEOMETRY
OPTICAL PROPERTIES
OXIDATION
PHOTOELECTRON SPECTROSCOPY
STABILIZATION
TRANSITION ELEMENTS