6533b7d2fe1ef96bd125ecce

RESEARCH PRODUCT

Deformation of the octahedral coordination of the Sb(III) atom in the structure of bis(1,2,4-triazolium) pentachloroantimonate(III) (C2H4N3)2[SbCl5]

subject

description

In the title compound the [SbCl 6] 3- octahedra show high variations in their Sb-Cl bond lengths and Cl-Sb-Cl angles. There are two crystallographically non-equivalent (C 2H 4N 3) + 1,2,4-triazolium cations in the crystal structure. They are located inside the cavities formed by the [{SbCl 5} 2-] n inorganic structure. The [{SbCl 5} 2-] n chains and (C 2H 4N 3) + cations are connected with each other by the N-H...Cl and C-H...Cl hydrogen bonds. Only two chloride atoms are involved in the N-H...Cl hydrogen bonds. The N-H...Cl interactions are responsible for the changing of geometries of Sb1-Cl2 and Sb1-Cl4 bonds and corresponding Cl-Sb-Cl angles. Their influence on the geometry of [SbCl 6] 3- octahedra are clearly visible in case of the terminal Cl2 atom, which takes part in three relatively strong N-H...Cl interactions. The presence of the hydrogen bonds leads to the large elongation of the terminal Sb1-Cl2 bond to the value typical for bridging Sb-Cl distances (3.072(1) Å). The elongation of Sb1-Cl2 bond leads to the shortening of Sb1-Cl1 bond located opposite to the value of 2.404(1) Å. To the best of our knowledge this is the first example of R 2SbCl 5 chloroantimonate(III) where such elongation caused by the hydrogen bonds has been found.