Bis(trimethylphosphine)silver(I) hexafluorophosphate.

In the title two-coordinate silver compound, [Ag(C(3)H(9)P)(2)]PF(6), the cation has crystallographically imposed mirror symmetry, and approximates very closely to 3m (D(3d)) symmetry with fully staggered methyl groups in the solid state. The Ag atom has a nearly linear coordination geometry, with a P[bond]Ag[bond]P angle of 178.70 (4) degrees. The Ag[bond]P bond lengths are 2.3746 (12) and 2.3783 (12) A, which are significantly longer than the Au[bond]P bond length of 2.304 (1) A in the analogous two-coordinate gold cation. The lack of intramolecular steric effects within the present cations containing trimethylphosphine (cone angle 118 degrees), compared with those in known cations containing trimesitylphosphine (cone angle 212 degrees), provides a better comparison of M[bond]P distances and thus more conclusive evidence that Au really is smaller than Ag.