Fibrous red phosphorus

Middle Pair of parallel interconnected five-sided tubes in fibrous red phosphorus, with... 

Fig. 15.3 (a) The tetrahedral P4 molecule found in white phosphorus, (b) Part of one of the chain-like arrays of atoms present in the infinite lattice of Hittorf s phosphorus the repeat unit contains 21 atoms, and atoms P and P" are equivalent atoms in adjacent chains, with chains connected through P —P" bonds. The same chains are also present in fibrous red phosphorus, (c) Part of one layer of puckered 6-membered rings present in black phosphorus and in the rhombohedral allotropes of arsenic, antimony and bismuth. 

For recent details, see H. Haiti (1995) Angewandte Chetnie International Edition, vol. 34, p. 2637 - New evidence concerning the structure of amorphous red phosphorus M. Ruck et al. (2005) Angewandte Chetnie International Edition, vol. 44, p. 7616 - Fibrous red phosphorus . 

Reaction 15.10 yields Li2Pi6, while Li3P2i and Li4P26 can be obtained by altering the ratio of P4 LiPH2. The structures of the phosphide ions [Pie], 15.9, [P2i], 15.10, and [P26] are related to one chain in Hittorf s and fibrous red phosphorus (Figure 15.3b). 

Brown phosphorus has been obtained by condensing phosphorus vapour containing P molecules on to a surface at liquid nitrogen temperatures. Above 0°C it changes to a mixture of red and white. Fibrous red phosphorus is a red-brown form of phosphorus which contains tubes of pentagonal cross section (similar to those in Hittorf s variety) and all of which lie parallel to the fibre direction [39,48]. 

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