Synthesis, crystal structure and thermal decomposition of certain metal thiocyanates and organic thiocyanates

Abstract

The aim of this study was to synthesize new metal and organic thiocyanates that in addition might be suitable for applications in the field of nonlinear optics (NLO). Thus, a concise overview of nonlinear optics and different types of materials adequate for use in NLO is given in the literature part. The theory of nonlinear optics is extensive and it is only functional to cover the basic concepts of the theory. The thiocyanate ion and its coordination modes are discussed in general and in relation to the ion being a part of a NLO suitable material. Crystal structures and thermal decomposition of various metal thiocyanates and aromatic quaternary ammonium bromides and chlorides, as starting materials of the thiocyanates in the experimental part, are described. In the experimental part syntheses and crystal structures of six new metal thiocyanates and five new organic thiocyanates are reported. Unknown thermal decomposition routes of two synthesized metal thiocyanates and five synthesized organic thiocyanates besides of three metal thiocyanates with known structures (KSCN, CsSCN, CsCd(SCN)₃) are presented. The new thiocyanates synthesized are as follows: KPb(SCN)₃, K₆Pb(SCN)₈·2H₂O, Cs₆Zn₃(SCN)₁₂·8H₂O, Cs₄Cd(SCN)₆·2H₂O, Cs₂Hg(SCN)₄, Cs₂CdAg₂(SCN)₆, [Bz₂Me₂N]SCN, [Bz₂Me₂N]SCN-H₂O, [Me₂(2-MeBz)₂N]SCN, [Me₂(3-MeBz)₂N]SCN, [Me₂(4-MeBz)₂N]SCN.