Reflectivity and(dRdE)Rof GaP between 2.5 and 6.0 eV

The reflectivity and logarithmic derivative of the reflectivity of GaP at $T=2\mathrm{} \mathrm{and} 300$ K are reported. A ${\Delta }_0$ spin-orbit splitting of 80 ± 1 meV is obtained, in agreement with earlier transmission data. The $E_1$, $E_1+{\Delta }_1$ splitting is resolved and the value ${\Delta }_1=50\mathrm{}\pm 5$ meV is found. Reflectivity structures not observed previously have been seen between 4.5 and 6.0 eV.