Die Packung in drei verschiedenen Strukturtypen für Verbindungen (AsPh₄)₂MCl₅X · 2CH₂Cl₂.

Abstract

Compounds (AsÇh^MClsX·2CH 2 C1 2 (M = metal; X = 0, NO or Cl) are shown to crystallize in three different structure types with essentially equal packing density. In type I, two AsPh/ ions are paired around an inversion center in such a way that three phenyl groups of one ion face three phenyl groups of the other ion in a staggered arrangement; the fourth phenyl group points away from the inversion center. The (AsPh^ ) 2 groupings are aligned to give parallel rows in which contacts between the fourth phenyl groups exist. Structure typeII has layers of AsPlvj!" ions; within the layer, pairs of AsPh^ ions have a similar arrangement as in type I. In type III, half of the AsPh^ ions form layers as in type II while the remaining AsPh/ ions form separated (AsPh/) 2 pairs. The MC1 5 X 2~ ions and CH 2 C1 2 molecules fill gaps between the cation arrangements ; the CH 2 C1 2 molecules are associated to the anions via weak hydrogen bonds. The crystal structures of (AsPh^TiCle · CH 2 C1 2 (type I) and (AsPh^UCU · 2CH 2 C1 2 (type III) were determined and refined with X-ray diffraction data. The latter compound also crystallizes in type I. Crystal data: Type I (TiCl|~) a = 1759, ò = 1563, c = 1919 pm, 0 = 98.58°, space group P2Jc, Z=4; type III (UCll -) a = 1052,_è = 1221, c = 2294 pm, α = 98.29, i? = 104.63, y = 101.81°, space group PI, Ζ =_2; typeII (found with ReOCl §~ and WOCl^") is triclinic, space group Pi, Z= 1. EinleitungTetraphenylphosphonium-und arsoniumionen werden häufig benutzt, um anionische Komplexe zu stabilisieren und in kristalliner Form zu isolieren.Brought to you by | University of California Authenticated Download Date | 6/8/15 1:12 AM

Crystal supramolecular motifs. Ladders, layers and labyrinths of Ph4P+ cations engaged in fourfold phenyl embraces

“…The main categories of multiple phenyl embrace are the sixfold phenyl embrace or 6PE † containing six edge-to-face (ef) attractions involving three phenyl rings from each Ph 4 P ϩ , first identified by Muller,7 and two types of fourfold phenyl embrace or 4PE. † In the orthogonal fourfold phenyl embrace (O4PE) the two C-P-C planes for the four phenyl rings are approximately orthogonal and engaged in four ef interactions, while in the parallel fourfold phenyl embrace (P4PE) these two C-P-C planes are approximately parallel and the motif comprises one off and two ef interactions.…”