Synthesis and crystal structure of K2Mn3S4

Single crystals of K2Mn3S4 have been prepared by a fusion reaction of potas sium carbonate with manganese in a stream of hydrogen sulfide at 900 degree s C. K2Mn3S4 crystallizes in a new monoclinic layered structure type (P2/c, a = 7.244(2) Angstrom, b = 5.822(1) Angstrom, c = 11.018(5) Angstrom, beta = 112.33(3)degrees, Z = 2) which can be described as a stacking variant of the orthorhombic Cs2Mn3S4 structure type. Measurements of the magnetic sus ceptibilities show antiferro-magnetic interactions.