Unsupported intermolecular argentophilic interaction in the dimer of trinuclear silver(I) 3,5-diphenylpyrazolates

The reaction of a solution of sodium 3,5-diphenylpyrazolate, Na[Ph2pz], with Ag(tht)NO3 in dichloromethane affords thin needles of unsolvated and light-stable dimer of trimers [Ag3(μ-3,5-Ph2pz)3]2. The complex is characterized by X-ray crystallography and elemental analysis. The two trimers are rotated anti to each other. Three silver atoms bridged through exobidentate pyrazolate groups form a slightly puckered nine-membered ring with the shortest Ag⋯Ag intramolecular interaction in the metallocycle of 3.3571(8) Å. The other two silver centers are weakly interacting, Ag(3)⋯Ag(1) = 3.49 Å and Ag(3)⋯Ag(2) = 3.52 Å. The intermolecular interaction between the two trimers is Ag⋯Ag = 2.9712(14) Å. Packing diagram shows the dimer of trimer units are independent. Density Functional Theory calculations show that the M⋯M interaction is due to dispersion forces. [Ag3(μ-3,5-Ph2pz)3]2 crystallizes in the monoclinic space group C2/c with a = 22.169(4), b = 15.269(3), c = 22.482(5) Å, β = 103.69(3)° and V = 7394(3) Å3.