title: A reversible polymorphic phase change which affects the luminescence and aurophilic interactions in the gold (I) cluster complex, [mu3-S(AuCNC7H13)3](SbF6).
abstract: Crystallographic examination of [mu3-S(AuCNC7H13)3](SbF6) shows that it undergoes a reversible phase change from orthorhombic to monoclinic upon cooling. At 190 K, the structure shows that two cations self-associate to form a pseudo-octahedral array of six gold atoms connected by both intra- and interionic aurophilic interactions. On cooling, the clusters become less symmetric, and in one, the interionic Au...Au separations increase, while they decrease in the second cluster. The luminescence of crystalline [mu3-S(AuCNC7H13)3](SbF6) shows corresponding changes in emission, with two emissions of similar lifetimes but with different excitations at 77 K, but only a single emission at 298 K. In contrast, [mu3-S(AuCNC6H11)3](PF6), which has a similar structure to that of the high-temperature form of [mu3-S(AuCNC7H13)3](SbF6), does not undergo a phase change or change in its luminescence upon cooling.
authors.affiliation: Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA.
authors.forename: Emily M
authors.initials: EM
authors.lastname: Gussenhoven
authors.forename: James C
authors.initials: JC
authors.lastname: Fettinger
authors.forename: David M
authors.initials: DM
authors.lastname: Pham
authors.forename: Mark A
authors.initials: MA
authors.lastname: Malwitz
authors.forename: Mark M
authors.initials: MM
authors.lastname: Malwitz
authors.forename: Alan L
authors.initials: AL
authors.lastname: Balch