Anomalous band gap bowing in AlAs1-xNx alloys

We have employed a first principle self consistent linear muffin tin orbita l method in the local density approximation to calculate the electronic str ucture of the nine AlAslxNx alloys with x = 0.0, 0.125, 0.25, 0.375, 0.50, 0.625, 0.75, 0.875 and 1.0. The lattice parameter shows a non linear behavi our with the concentration of N-atoms. A quite smaller gap appears in the n eighbourhood of x = 0.125 concentration of N-atoms.. The state lying at the CBM, which is composed of N-s, Al(s,p), As-s descends into the fundamental gap filling it partially. For the random alloys the band gap also shows an omalous bowing. (C) 1999 Published by Elsevier Science Ltd.