High-Pressure Synthesis and Crystal Structure of the Sulfur-Richest Chromium Sulfide CrS₃ Composed of Cr(III) and Disulfide Ions

Abstract

The new binary chromium sulfide CrS 3 has been synthesized by reaction of Cr 3 S 4 and sulfur mixtures at 800 °C and 13 GPa. CrS 3 crystallizes in an orthorhombic unit cell with a = 4.6742(7) Å, b = 5.7315(8) Å, c = 10.603(2) Å, and V = 284.873(4) Å 3 . It has a novel structure composed of Cr 2 S 10 edge-shared octahedral dimers, which share all of their corners to form a three-dimensional structure. All of the sulfur atoms form S 2 2− disulfide ions with a S−S distance of 2.063(5) or 2.068(8) Å. The structure of CrS 3 is a derivative of the crystal structure of marcasite FeS 2 , in which one in three metal sites of the marcasite structure is vacant in the CrS 3 structure.

Accessing Mg‐Ion Storage in V2PS10 via Combined Cationic‐Anionic Redox with Selective Bond Cleavage

“…Refinement of the S(15) and S(20) atomic positions reveals that these sites shift significantly from their original positions during formation of Mg 0.51 V 2 PS 10 . Typical disulphide distances range from $${\approx }$$ 1.9–2.18 Å with an ideal bond length of 2.05 Å [50–52] . This S(15)−S(20) inter‐atomic distance increases by 0.32 Å (15.2 %) from 2.081(17) Å in V 2 PS 10 to 2.397(13) Å in Mg 0.51 V 2 PS 10 (Figure 2c–d, Table S11), suggesting that the bridging disulphide bond in the [P 2 S 8 ] bitetrahedral unit of V 2 PS 10 is broken as a result of Mg insertion.…”

“…Typical disulphide distances range from �1.9-2.18 Å with an ideal bond length of 2.05 Å. [50][51][52] This S(15)À S(20) inter-atomic distance increases by 0.32 Å (15.2 %) from 2.081(17) Å in V 2 PS 10 to 2.397(13) Å in Mg 0.51 V 2 PS 10 (Figure 2c-d, Table S11), suggesting that the bridging disulphide bond in the [P 2 S 8 ] bitetrahedral unit of V 2 PS 10 is broken as a result of Mg insertion. This reduces (S 2 ) 2À to 2S 2À and creates space for Mg insertion sites between the columns of VS 8 polyhedra originally connected by the S 3 PSÀ SPS 3 bond.…”