title: Exploring the thermochromism of sulfite-embedded polyoxometalate capsules.
abstract: The Dawson-type polyanion [α-Mo(18)O(54)(SO(3))(2)](4-), with two SO(3)(2-) templates embedded inside a polyoxomolybdate(vi) cage, exhibits thermochromism over an exceptionally wide temperature range (∼500 K). The temperature dependence of the cluster structure, established from X-ray crystallography, IR and Raman spectroscopy and DFT calculations, is related to a decreasing HOMO-LUMO gap in the near UV with increasing temperature. We postulate this is due to geometrical changes that affect both the occupied and unoccupied frontier molecular orbitals of this cluster anion.
authors.affiliation: WestCHEM, Department of Chemistry, University of Glasgow, Joseph Black Building, University Avenue, Glasgow G12 8QQ, UK.
authors.forename: Ryo
authors.initials: R
authors.lastname: Tsunashima
authors.forename: De-Liang
authors.initials: DL
authors.lastname: Long
authors.forename: Toru
authors.initials: T
authors.lastname: Endo
authors.forename: Shin-ichiro
authors.initials: S
authors.lastname: Noro
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Akutagawa
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Nakamura
authors.forename: Raul Quesada
authors.initials: RQ
authors.lastname: Cabrera
authors.forename: Paul F
authors.initials: PF
authors.lastname: McMillan
authors.forename: Paul
authors.initials: P
authors.lastname: Kögerler
authors.forename: Leroy
authors.initials: L
authors.lastname: Cronin