9,9,10,10-Tetrafluoro-1,3,5,7-tetrathio-2,4,6,8-tetraaoxa-1,3,5,7-tetraphosphatricyclo[3.3.1.13,7]decane, P4O4(CF2)2S4: a cage structure related to P4O6

Abstract

The title structure is formally derived from the P406 cage structure by sulfuration of the P atoms (as in the known structure P40654) and replacement of two bridging O atoms by CF2 groups. The molecule possesses crystallographic twofold symmetry. The main effect of introducing the CF2 groups is to widen the remaining P--O--P angles and shorten the P--O bonds; the P---C bonds are longer than the P--O bonds and the P--C~P angles narrower than the P--O--P angles.Despite the apparent suitability of cage structures for rigid-body libration corrections, Rlib (Schomaker & Trueblood, 1968) was high (0.11), perhaps because of the CF2 groups, and the associated bond-length corrections of 0.003-0.004 A may not be reliable. We prefer to discuss uncorrected bond lengths.