title: Aromaticity in stable tiara nickel thiolates: computational and structural analysis.
abstract: Quantum chemical calculations as well as crystallographic analyses show that the Ni(n) rings in the tiara Ni thiolates, [NiS2]n and [Ni(SR)2]n (n = 3-6), have highly symmetric polygonal structures. We find that such structural features primarily arise from the effective delocalization of the d-orbital electrons across the Ni(n) rings leading to bond length equalization and thereby aromaticity. We introduce the d-orbital aromaticity for the first time to explain the experimentally observed polygonal structures of these cyclic metal rings bridged by thiol linkages.
authors.affiliation: Theoretical Sciences Unit, Jawaharlal Nehru Center for Advanced Scientific Research, Jakkur P. O, Bangalore-560064, India.
authors.forename: Ayan
authors.initials: A
authors.lastname: Datta
authors.forename: Neena S
authors.initials: NS
authors.lastname: John
authors.forename: G U
authors.initials: GU
authors.lastname: Kulkarni
authors.forename: Swapan K
authors.initials: SK
authors.lastname: Pati