Binary Phosphorus-Sulfur and -Selenium Rings

7 PNICTOGEN-CHALCOGEN RINGS 11.7.1 Binary Phosphorus-Sulfur and -Selenium Rings 

Binary phosphorus-sulfur and -selenium compounds have polycyclic structures.The most common examples are P4E3 and P4E10 (E = S, Se). The 

Sulfur-rich binary P-S anions of the type [S2P(p-S )2PS2] form monocyclic structures with sulfide or disulfide bridging units ( = 1, 2) (11.39). Another type of cyclic P-S anion with the general formula [(PS2) ] is formed in the reaction of white phosphorus with polysulfides in a non-aqueous medium these anions have homocyclic structures with two exocyclic sulfur atoms attached to each phosphorus atom, e.g. [P4Ss] (11.40).  

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