Theoretical electronic structures and relative stabilities of the spinel oxynitridesM3NO3(M=

Elastic constants of oxynitride aluminum spinel phases

“…4, we now show the calculated density of states for each of these systems. And as with the charge-density contours, we observed a similar trend in energy gaps with Al 3 NO 3 and Al 23 [11]. b Ref.…”

“…This gave an estimated calculational error in the total energy of 0.05 eV/atom. Guided by the work of Fang et al [12], and our recent study on the ideal spinel (Al 8 ½Al 16 N 8 O 24 ) [11], we started from the lowest energy model of the ideal Al-O-N system with 56-atom unit cell that comprises a spinel structure as shown in In Fig. 1, we have shown only the unit cell with vacancies at the octahedral sites.…”

“…The three stoichiometric compounds of Al-O-N are Al 3 NO 3 (or Al 24 N 8 O 24 ), Al 23 N 5 O 27 and Al 22 N 2 O 30 . The ideal Al 3 NO 3 , in its stable state is an incompressible structure and could have the potential to be a novel hard material with possible application as industrial abrasive device [11,12]. Al 23 N 5 O 27 [13][14][15] is an advanced polycrystalline ceramic material for refractory in industries and for protective windows in optical systems [16].…”

Anion ordering in spinel-type gallium oxonitride

“…Several studies were carried out regarding ternary nitrides/oxonitrides [6][7][8][9][10][11][12][13][14][15] in an effort to tailor the highly desirable mechanical and electronic properties associated with spinel nitrides to suit specific applications.…”

“…Previously, theoretical studies show that gallium oxonitride with ideal structure (Ga 3 O 3 N) might have a band gap comparable to that of w -GaN or slightly larger 10,12 allowing potentially useful electronic applications. Direct band gap values calculated using the local density approximation (LDA) and generalized gradient approximation (GGA) are 1.72 eV and 1.37 eV, respectively 13 . However, it is well known that LDA and GGA calculations underestimate the band gap 20 and the actual band gap value of Ga 3 O 3 N may be as large as 4 eV 10 .…”