N₂ positively charged defects in diamond. A quantum mechanical investigation of the structural, electronic, EPR and vibrational properties

Abstract

Structural, EPR and vibrational characterization of the N2, N+2 and N++2 defects in diamond from ab initio quantum-mechanical calculations with the CRYSTAL code.

Interstitial defects in diamond: A quantum mechanical simulation of their EPR constants and vibrational spectra

“…Recent applications to various defects (substitutional N, or Ns, 31 VN − 2 , 32 N + 2 33 ) have confirmed that the present approach is able…”

“…It was designed to better describe the core electrons, but the valence shells are also richer, with exponents of the most diffuse s and p functions of C and N set to 0.169 bohr −2 and 0.212 bohr −2 , respectively. 37 This combination of the B3LYP functional and the 6-31G-J * basis set has been shown to provide accurate results for the EPR data of three defects in diamond, namely, Ns, 31 VN − 2 (the negatively charged form of VN 2 , with two nitrogen atoms around a vacancy), 32 and N + 2 , the positively charged form of the so called A defect (two vicinal substitutional N atoms), 33 where in all three cases, the spin state is a doublet.…”

The role of spin density for understanding the superexchange mechanism in transition metal ionic compounds. The case of KMF3 (M = Mn, Fe, Co, Ni, Cu) perovskites

“…Chem. Phys., 2022, 24, 12950-12960 | 12959 (substitutional nitrogen), 31 VN 2 À (negatively charged, with a vacancy and two nitrogen atoms as first neighbors) 32 or N 2 + (two vicinal substitutional nitrogen atoms, positively charged) 33 defects in diamond, that can be compared with experimental EPR results (see for example ref. [34][35][36][37]; (b) In determining the stability of the AFM phases with respect to the FM one in TM compounds, through the superexchange mechanism.…”

Vibrational Analysis of Paraelectric–Ferroelectric Transition of LiNbO3: An Ab-Initio Quantum Mechanical Treatment

“…As shown by a previous paper, the combined use of the B3LYP functional and the triple ζ basis set [20][21][22][23][24][25][26] provides very accurate results for the vibrational spectra, in terms of both wavenumbers and intensities [25,[27][28][29][30][31]. The exchange and Coulomb infinite lattice series can be modified through five parameters, T i , which were set to 8 (T 1 -T 4 ) and 16 (T 5 ).…”