trans-Tetra-carbonyl-bis-(tri-phenyl-phosphane-κP)molybdenum(0)

The well known title compound, trans-[Mo(C18H15P)2(CO)4], has not been studied previously by X-ray crystallography, unlike its cis isomer. The complex possesses crystallographically imposed inversion symmetry, with the Mo atom residing on an inversion centre (1a Wyckoff position). The two tri-phenyl-phosphane groups are arranged in a staggered orientation. Each of the phenyl groups exhibits significantly different Mo-P-C-C torsion angles ranging from 2.6 (2) to 179.4 (1)°, most likely due to steric inter-actions based upon their positions relative to the carbonyl ligands.