Anab InitioStudy of the NH2+Absorption Spectrum

An ab Initio Study of the Ã2Π State and the Ã2Π←X̃2Σ+ Electronic Transition of MgNC

“…Previous studies carried out with the RENNER program system have been concerned with Renner-degenerate electronic states for which at least the lower component has a barrier to linearity (see Refs. (18)(19)(20)(21)(27)(28)(29)(30)(31)). For such states, the pattern of rovibronic energies is crucially dependent on the shapes of the potential energy surfaces involved, and it can only be obtained from detailed numerical calculations.…”

A Theoretical Investigation of the Renner Interactions and Magnetic Dipole Transitions in the ÖX̃ Electronic Band System of HO2

“…(2) and (38) of (10). The RENNER program was recently extended to enable the calculation of the electric dipole intensities of transitions between the rovibronic levels of two electronic states that are in Renner interaction (14,15). For the present work we have made some further modifications in order to calculate the positions and intensities of the magnetic dipole transitions as well.…”

Nitrenium Ions and Problem of Direct Electrophilic Amination of Aromatic Compounds

“…Up to now, quantum-chemical calculations were performed for a wide variety of nitrenium ions: NH 2 + [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40], MeNH + [22,24,25,30,36,41], Me 2 N + [22,24,25,30,41], MeAcN + [22], (CH 2 ) 2 N + [42], (CH 2 ) 4 N + , (CH 2 ) 5 N + [22,24,25], (XCH=CH)MeN + (X = H, Cl) [25], (CH) 2 N + , CHN 2 + [43], (CH) 6 N + [44], XN 3 + (X = O, S, Se, Te) [45], XNH + (X = NH 2 , PH 2 , OR, SH, Cl, F, Br, I, CN, NC 2 ) [23,27,28,32,34,36,40,46], X(CHO)N + [X = N, NH 2 , PH 2 , OR, SH, Ph(CH 2 ) n O] …”

“…Unsubstituted nitrenium ion H 2 N + (3) exists mainly in the triplet state, and the energy difference between the singlet and triplet states was estimated at 89-152 kJ/mol [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40]. The best agreement with the experimental value (∆E ST = 125.9 kJ/mol [88]) was obtained by ab initio calculations (∆E ST = 125.8 kJ/mol, CASSCF-MRCI + ZPVE; ∆E ST = 125.6 kJ/mol, TZ2P(f,d)CASSCF(6,6)-SOCI + ZPVE [33] 149.4°0 .1025 nm 475 calculations [MP4(SDTQ)/6-311 + G(3d2f,2p)// MP2/6-311 + G(3d,2p)] showed that both singlet and triplet states of H 2 N + ion have an angular structure and that the HNH angle in the triplet state is considerably greater [24].…”