Trilithium thio-arsenate octa-hydrate

Area of Science:

• Inorganic Chemistry
• Crystallography
• Materials Science

Background:

• Understanding the structural motifs and bonding in hydrated inorganic salts is crucial for materials science.
• Lithium thioarsenates are of interest due to their potential applications and unique coordination chemistry.

Purpose of the Study:

• To elucidate the crystal structure of lithium thioarsenate octahydrate, Li3AsS4·8H2O.
• To characterize the coordination environment of lithium and the bonding interactions within the crystal lattice.

Main Methods:

• Single-crystal X-ray diffraction was employed to determine the atomic arrangement.
• Analysis of bond lengths, coordination geometries, and hydrogen bonding networks was performed.

Main Results:

• The structure features infinite cationic [Li3(H2O)8](3+) chains along [001], cross-linked by tetrahedral AsS4(3-) anions.
• Lithium ions exhibit diverse coordination, with Li-O bond lengths ranging from 1.876(5) to 2.319(5) Å.
• The structure is stabilized by O-H⋯S hydrogen bonds, with no alkali-sulfur or O-H⋯O bonds observed, distinguishing it from related compounds.

Conclusions:

• Li3AsS4·8H2O possesses a unique chain structure with complex lithium-oxygen coordination polyhedra.
• The hydrogen bonding network plays a critical role in stabilizing the overall crystal structure.
• The absence of direct alkali-sulfur interactions suggests specific bonding preferences in this thioarsenate hydrate.