KNiPS4: A New Thiophosphate with One- and Two-Dimensional Structural Arrangements

Abstract

Single crystals of a new ternary thiophosphate, KNiPS4, have been synthesized by reaction of the elements in an evacuated silica tube at 873 K for two weeks. The structure was solved in the tetragonal space group P 42/mnm with a = 8.2538(4) Å, c = 10.7553(6) Å, and Z = 4. The refinements led to R = 0.0250 (Rw = 0.0190) for 425 independent reflections and 26 variables. The structure of KNiPS4 consists of nickel in square planar sulfur coordination linked by edge-sharing PS4 tetrahedral groups to produce one-dimensional chains. The chains are aligned in a parallel manner to form layers perpendicular to the c-axis and they are separated by layers of potassium. Tight-binding band structure calculations suggest that the nickel atoms should be in a low-spin Ni11 state resulting in an overall charge balance of KINiIIPV(S-II)4. UV-visible spectroscopic measurements indicate KNiPS4 to be semiconducting.