Implications of the crystal structure of the ammonia solvate [Au(NH 3)2]Cl·4NH3

Abstract

Crystals of diammine gold(I) chloride ammonia (1/4), [Au(NH 3)2]Cl·4NH3, have been grown from solutions of AuCl in liquid ammonia. The X-ray diffraction analysis (at 123 K) has shown that the crystals feature an extensive network of hydrogen bonds between the [H3N-Au-NH3]+ cations (with C i symmetry) and the Cl- anions, including also the ammonia molecules. There is no evidence for an emerging increase of the coordination number of the gold atom by adopting another ammonia molecule or by approaching a chloride anion. Moreover, the geometry of two distant and angular N-H···Au contacts is not a strong support of hydrogen bonds recently amply discussed in the literature. © 2013 American Chemical Society.