1	FPZ	Triphenylphosphane	1.000
2	B5J	Methyltriphenylphosphonium	0.950
3	XIS	4-diphenylphosphanylbenzoic acid	0.864
4	P4P	Tetraphenylphosphonium	0.760
5	3JE	Triphenyl(phenylethynyl)phosphonium	0.704