Document Type


Publication Date

Spring 3-2014


Combination of CuI and tetrahydrothiophene (THT) in MeCN or neat THT produces various phases depending upon experimental conditions. Green luminescent product (CuI)4(THT)2 (1) consists of Cu4I4 cubane units knit into a 3-D network by m2-THT ligands. Yellow luminescent (CuI)10(THT)7(MeCN) (2) contains {[Cu4I4(THT)](m2-THT)2(Cu2I2)(m2-THT)2[Cu4I4(NCMe)]} “rungs” linked into 1-D ladders by pairs of m2-THT ligands. Two molecular (CuI)4(THT)4 phases were found: orange luminescent 3a and dull yellow luminescent 3b. Triclinic 3b is the more stable phase at 25 °C, but undergoes endothermic transformation to monoclinic 3a at 38 °C. 3a transforms to a triclinic phase (3a') that retains orange emission at −60 °C. Non-emissive (CuI)3(THT)3•MeCN (4) is a 2-D sheet structure in which Cu3(THT)3 rings are linked in trigonal directions by rhomboid Cu2I2 dimer units. The previously reported (CuI)2(THT)4 (5) is a molecular dimer. Temperature and mixing ratio domains for the formation of the CuI-THT phases from MeCN are presented. Luminescence in 1, 2, 3a, and 3b is rationalized based on varying degrees of halide-to-metal charge transfer (XMCT) and metal-centered (MC) behavior. Low temperature spectra reveal reversible changes, including modest red shifts for 1 and 2, and splitting into two excitation/emission band pairs for 3a and 3b.

Journal Title

Crystal Growth & Design







Publisher Statement

This document is the unedited author's version of a Submitted Work that was subsequently accepted for publication in Crystal Growth & Design, copyright © American Chemical Society after peer review. To access the final edited and published work see