The synthesis and characterisation of tris(N,N′-diethylmonothiocarbamato)indium(III) [In(SOCNEt2)3] and diethyl(N,N′-diethylmonothiocarbamato)indium(III) [Et2In(SOCNEt2)]n: potential precursors for the growth of indium sulfide by low pressure metal organic chemical vapour deposition

Abstract

The indium complexes [In(SOCNEt₂)₃] 1 and [Et₂In(SOCNEt₂)]_n 2, containing the N,N′-diethylmonothiocarbamato ligand, have been prepared. Complex 1 is a colourless crystalline solid. Complex 2 was prepared by the comproportionation of 1 with triethylindium. The tris(diethylmonothiocarbamate) complex 1 is a distorted trigonal prismatic monomer with the unusual meridional configuration. The mixed alkyl diethylmonothiocarbamate 2 is a colourless polymeric solid, where the metal centre is found in a distorted trigonal bipyramidal geometry. Chain propagation occurs through In–O bonds. Both complexes have been characterised by their single-crystal X-ray structure determinations. Complex 1 can be used for the deposition of highly oriented films of β-In₂S₃ by low pressure metal-organic chemical vapour deposition (LPMOCVD) at temperatures ranging from 350–500 °C on borosilicate glass substrates.