in neat (no solvent) byproducts: phosphorus hydrides; dismutation of P2H4; formation of phosphorus hydrides with composition P(n)H(n+2), P3H5 and cyclic phosphorus hydrides with composition P(n)H(n);;

in not given byproducts: phosphorus hydrides; Irradiation (UV/VIS); dismutation of P2H4 by irradiation forming PH3, P3H5 and phosphorus hydrides;; observed by Raman spectroscopy;;

in water -78°C, then -40°C; followed by NMR;