Exploring structure-property relationships of silver 4-(phenylethynyl) pyridine complexes

Abstract

Silver(salts demonstrate a strong preference for forming linear complexes when reacted with 4-(phenylethynyl)-pyridine (pep). The packing of these complexes was found to be strongly influenced by the counteranions, namely PF6-,BF4-, NO2-, NO3-, MeCO2-, CF3CO2-, MeSO3-, Tos-and SCN-. This study evaluates a family of twelve solid-state structures that exhibit varying metal-to-ligand ratios, [Ag(pep)2][PF6]· MeCN, [Ag(pep)2][PF6], [Ag(pep)2][BF4], [Ag(pep)2][Ag(NO2)2], [Ag(pep)2][NO3]·2H2O, [Ag(pep)2][Ag(NO3)2], [Ag(pep)2(MeCO2)]· 3H2O, [Ag(pep)2][CF3CO2],[Ag(pep)2][CF3SO3], 2{[Ag(pep)2]-[Tos]}·pep and [Ag(pep)(SCN)]. This family has enabled general trends and noteworthy packing-induced structure-property relationships to be elucidated. Highlights include two instances of single-crystal-to-single-crystal transformations, one of which occurs with a colour change. This change in crystal colour has been further explored using first-principles computational modelling.