Abstract: The title crystal is yellow in collour,belonging to the monoolinic system.The space group is P_(2_1)/n with following unit cell parameters: a=0.8253(5), b=2.1018(10), c=2.1531(17) nm; β=90.89(6)(°), V=3.734 (7) nm, Z=4. D_calc=1.934 gcm~(-3).
The crystal structure was solved by the direct method(MULTAN-82)and refined by full-matrix least-squares to a final conventional R factor of 0.061. The results reveal that the crystal structure consists of neutral trinuclear Mo cluster molecules, in which three independent Mo atoms form an equilateral triangle with an average side length of 0.2631 nm, corresponding to a Mo-Mo single bond. On one side of the triangle one μ_3-S atom binds the three Mo atoms together to form a monocapped trinuclear cluster. In addition, three S_2 radicals acting as μ_2 bridges are located between each two Mo atoms. Each Mo atom is also coordinated by two terminal S atoms of [S_2P(OEt)_2]~- radical so as to complete a distored pentagonal bipyramid configuration.