Table 2. Compilation of θ and φ Angles in the Structures Discussed Here^a.

structure		θ [deg]	φ [deg]
I	A	166.85
	B	154.43
II	A	167.33	78.06
	B	166.14	79.26
III		161.31	69.58
IV	A	169.81	78.34
	B	168.45	69.18
V		166.01	78.48
VI		161.80	75.01

^aLabels A and B refer to the crystallographically independent molecules.