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[en] The molecular geometries and dissociation energies of AnO (An = Bk–Lr) molecules were first obtained at the coupled-cluster single-, double-, and perturbative triple-excitations [CCSD(T)] level of theory. Four hybrid functionals, B3LYP, M06-2X, TPSSh, and PBE0, were also employed in the calculations for the sake of comparison. In comparison of the CCSD(T) results, B3LYP, TPSSh, and PBE0 functionals can obtain more appropriate results than M06-2X and MP2. The analyses on molecular orbitals show that the 7s, 6d, and 5f atomic orbitals of actinide (An) atoms participate in the bonding of An–O bonds. The partial covalent nature between An and O atoms is revealed by QTAIM analyses. (paper)
[en] Full vibrational spectra and dissociation energies are studied for the 0u-, B''Iu states of I2, X 1Σg+ of Br2 and A'3Π(2u) of Cl2. The full vibrational spectra were computed using a standard algebraic method (AM) with available experimental vibrational energies as input parameters. The dissociation energies were estimated using an analytical formula and the three highest AM vibrational energies. Prior to the present work, reliable high-lying vibrational energies and dissociation energies of these states were difficult to obtain experimentally and theoretically.
[en] In this paper, a new spectroscopic and analytical potential energy function (APEF) investigation on the electronic state of the Na85Rb molecule is reported. This research is conducted by using the 4-terms variation algebraic energy consistent method (VAECM(4)) with a variable parameter λ. The calculated full vibrational energies of 78 levels are used in a global linear reduction to molecular vibrational constants. With these new and improved vibrational constants, the potential energy curve and the vibrational force constants have been calculated. Precise values for the long-range parameters and the dissociation energy have been derived. The results obtained in this study also provide valuable reference data for other areas of researches on Na85Rb. (paper)
[en] Highlights: • Elastic properties of vanadate and V2O5-contained glasses were predicted. • Prediction has been carried out on the basis of Makishima–Mackenzie's theory. • Correlation between elastic moduli and compositional parameters was studied. • Dissociation energy was evaluated in terms of V–O and P–O single bond strength. • Good agreement between theoretical and experimental elastic moduli was achieved.
[en] It is shown that energy must be conserved by the dissociation of an elementary particle. The energy deficit by a dissociation behaves as a basic concept. The binding energy of the deuteron is reproduced. 4 refs
[en] Indole-3-carbinol (I3C) is an indole compound with proven health benefits and thus potential preventive medicine and therapeutic applications. Here the origins of the substituent effects on the antioxidant activity of monosubstituted indole-3-carbinols (I3Cs) were studied in silico by calculating their thermochemical properties using the (RO)B3LYP/6-311++G(2df,2p)//B3LYP/6-311G(d,p) model chemistry. It was found that the electron withdrawing groups such as CF3, CN, COOH, COOMe can increase the bond dissociation energy (BDE) values of N–H bonds and decrease the BDE(C8–H) values, while the presence of the Br, Cl, F, Me, NMe2, NH2, NHMe, OH, OMe, Ph groups seems to decline the BDE(X-H)s (X = N,C). It is worth noticing that a sequential electron transfer mechanism is responsible for these I3Cs with the strong electron donating groups including NMe2, NHMe and NH2, while a hydrogen atom transfer mechanism is likely favored for the remaining monosubstituted I3Cs. The kinetic study according to the HAT mechanism showed that the CH3OO radical scavenging of 2-NMe2-I3C derivative has the highest rate constant (k = 1.93×1010M-1s-1) and it is higher than that of typical antioxidants i.e. Trolox or ascorbic acid. Thus, the results appear to suggest that the N-Br-I3C and 2-NMe2-I3C compounds are potential antioxidants. (author)
[en] Second electron affinities of AuN and AgN clusters and the dissociation energies for fission of the AuN2- and AgN2- dianions are calculated using the finite-temperature shell-correction method and allowing for triaxial deformations. Dianionic clusters with N>2 are found to be energetically stable against fission, leaving electron autodetachment as the dominant decay process. The second electron affinities exhibit pronounced shell effects in excellent agreement with measured abundance spectra for AuN2- (N<30), with appearance sizes na2-(Au)=12 and na2-(Ag)=24. (c) 2000 The American Physical Society
[en] The RKRV potential energy curves for the observed electronic states of gaseous monochlorides of beryllium, magnesium and calcium have been constructed using the method of Y B Rao and P Venkateswarlu (1962). The ground state dissociation energy of these molecules has been evaluated by curve fitting technique. (author)
[en] The calculation results of dissociation energies of biatomic molecules, formed with p-elements of groups 3 and 4 with p-elements of groups 6 and 7 of the periodic system according to hyperbola method are presented. The hyperbolic dependence of bond rupture energies of similar compounds of element isostructural atoms on the charges of their nuclei makes these values interconnected and creates a possibility for their forecasting. The dissociation energies of the molecules of GaS, GaSe, B(Al, Ca, In, Tl)-Po, B(Al, Ga, In, Te)- At, CTe, C(Si, Ge, Sn, Pb)-Po and C(Si, Ge, Sn, Pb)-At as well as Te-E1 (E=O, S, Se, Te, Po) have been given for the first time