Copper(I) Complexes Based on Pentamethylene Sulfide: Luminescence Thermochromism of Cu4I4(C5H10S)4

Three copper(I) complexes, [Cu8I8(PMS)(4)(MeCN)(2)](n) (1), Cu4I4(PMS)(4) (2), and Cu2I2(PMS)(4) (3) were prepared by the self-assembly reaction of mole ratio-controlled CuI and pentamethylene sulfide (PMS). Single crystal X-ray diffraction analyses displayed crystal structures of three complexes based on new S-shaped Cu8I8, cubane Cu4I4, and rhomboid Cu2I2 cluster units for 1-3, respectively. Crystal transformations between 1, 2, and 3 were controlled by the addition of PMS or Cul/acetonitrile. Luminescence properties of 1 and 2 were investigated. Complex 1 showed two very weak emission bands, which were assigned to HE band for lambda(max) = 415 nm and LE band for lambda(max) = 575 nm under ultraviolet irradiation (lambda(ex) = 355 nm). Complex 2 displayed luminescence thermochromism with a slightly hypsochromic shift from 572 to 565 nm (lambda(ex) = 355 nm).