The Hall mobility of electrons is calculated for In0.5Ga0.5P by using
the experimental values of the effective mass and the band gap, and th
e estimated values of other constants. The experimental results are ex
plained by taking the alloy scattering potential and the acoustic phon
on deformation potential to be 0.435 and 12 eV, respectively. It is co
ncluded that the experimental samples had impurity concentrations lyin
g mostly between 5 and 15 times the electron concentration. (C) 1998 A
merican Institute of Physics. [S0021-8979(98)05311-0].