title: Vapochromic and mechanochromic tetrahedral gold(I) complexes based on the 1,2-bis(diphenylphosphino)benzene ligand.
abstract: Tetrahedral gold(I) complexes containing the diphosphane ligand (dppb=1,2-bis(diphenylphosphino)benzene), [Au(dppb)(2)]X [X=Cl (1), Br (2), I (3), NO(3) (4), BF(4) (5), PF(6) (6), B(C(6)H(4)F-4)(4) (7)], and the ethanol and methanol adducts of complex 4, 8, and 9, were prepared to analyze their unique photophysical properties. These complexes are classified into two categories on the basis of their crystal structures. In Category I, the complexes (1-5) have relatively-small counter anions and two dppb ligands are symmetrically coordinated to the central Au(I) atom, and display an intense blue phosphorescence. Alternatively, the complexes (6-9) in Category II have large counter anions and two dppb ligands asymmetrically coordinated to Au(I) atom, and display a yellow or yellow orange phosphorescence. The difference in the phosphorescence color of the complexes between the Category I and II is ascribed to the change in the structure of the cationic moiety in the complex. According to DFT calculations, the symmetry reduction caused by the large counter anion of the complex in Category II gives the destabilization of HOMO (σ*) levels, leading to the red-shift of the emission peak. We have demonstrated that the symmetry reductions are responsible for the phosphorescence color alteration caused by external stimuli (volatile organic compounds and mechanical grinding).
authors.affiliation: Luminescent Materials Laboratory, RIKEN (The Institute of Physical & Chemical Research), Hirosawa 2-1, Wako-Shi, 351-0198 Japan. osawa@postman.riken.jp
authors.forename: Masahisa
authors.initials: M
authors.lastname: Osawa
authors.forename: Isao
authors.initials: I
authors.lastname: Kawata
authors.forename: Satoshi
authors.initials: S
authors.lastname: Igawa
authors.forename: Mikio
authors.initials: M
authors.lastname: Hoshino
authors.forename: Takeo
authors.initials: T
authors.lastname: Fukunaga
authors.forename: Daisuke
authors.initials: D
authors.lastname: Hashizume
mesh_terms: D001555:Benzene Derivatives / Q000737:chemistry*; D018360:Crystallography, X-Ray; D008024:Ligands; D049449:Luminescence; D015394:Molecular Structure; D050607:Organogold Compounds / Q000737:chemistry*; D063065:Organophosphonates / Q000737:chemistry*; D010777:Photochemistry; D052616:Solid Phase Extraction; D055548:Vapor Pressure
chemical_list: C519449:1,2-bis(diphenylphosphino)benzene; D001555:Benzene Derivatives; D008024:Ligands; D050607:Organogold Compounds; D063065:Organophosphonates