Geometry and binding energy

Collins, J.B. Schleyer, P.V. Binkley, J.S. Pople, J.A. Self-consistent molecular-orbital methods. XVII. Geometries and binding energies of second-row molecules. A comparison of three basis sets J. Chem. Phys. 64 5142-5151, 1976. 

Self-Consistent Molecular Orbital Methods. XVn Geometries and Binding Energies of Second-Row Molecules. A Comparison of Three Basis Sets J. B. Collins, P. von R. Schleyer, J. S. Binkley and J. A. Pople The Journal of Chemical Physics 64 (1976) 5142-5151... 

Three basis sets (minimal s-p, extended s-p and minimal s-p with d functions on the second row atoms) are used to calculate geometries and binding energies of 24 molecules containing second row atoms, d functions are found to be essential in the description of both properties for hypervalent molecules and to be important in the calculations of two-heavy-atom bond lengths even for molecules of normal valence. 

In concluding, we point out an essential role of vibrational spectra In theoretical studies. Total energy calculations yield quantities of much Interest, like equilibrium geometries and binding energies, which are not accessible In a direct experimental way. Only the vibrational quantities can be meaningfully compared with experiment and provide a way to assess the adequacy of these calculations. 

Second-Order Perturbation Theory A Test of Geometries and Binding Energies. 

All results on the CoP-02 systems are collated in Table VIII. Once again, the geometries and binding energy depend strongly on the method and model used. 

A preliminary molecular dynamics simulation was performed. To this end, SCF-MI and MO-VB calculations were carried out on water dimers and trimers and a new parameterisation of a NCC-like (Niesar-Corongiu-Clementi) [53] potential was accomplished [10d]. The 7s4p2d/4s2p small basis set proposed by Millot and Stone [40] was employed. The Hartree Fock limit results obtained in our previous work were reproduced using this compact basis set also equilibrium geometry and binding energy values compared well with the experimental results. 

Quantum chemical methods are valuable tools for studying atmospheric nucle-ation phenomena. Molecular geometries and binding energies computed using electronic structure methods can be used to determine potential parameters for classical molecular dynamic simulations, which in turn provide information on the dynamics and qualitative energetics of nucleation processes. Quantum chemistry calculations can also be used to obtain accurate and reliable information on the fundamental chemical and physical properties of molecular systems relevant to nucleation. Successful atmospheric applications include investigations on the hydration of sulfuric acid and the role of ammonia, sulfur trioxide and/or ions... 

Andersson, K. Roos, B. O. Multiconfigurational second-order perturbation theory a test of geometries and binding energies, Int. J. Quantum Chem. 1993,45, 591-607. 

Table 2.23 Equilibrium geometries and binding energies (uncorrected for BSSE) calculated for the linear water dimer at various levels of theory. ...

TABLE 9. Oxidation state, geometry and binding energies (eV) of compounds of nickeP ... 

Table 2 Geometry and binding energy for optimised linear water dimers...

In order to reveal the details of binding in alkaline-earth clusters, it is important to carry out a comparative study of binding in clusters of Be, Mg, and Ca. There are many publications, in addition to those cited above, devoted to calculations of alkaline-earth clusters (see Refs. [10-21] and references therein). But in most of these studies, different computational approaches were applied to calculate the geometry and binding energy. 

In Table II the results of our calculations [22] of the equilibrium geometry and binding energy together with the published data are presented. A comparison with literature data indicates a quite satisfactory agreement. The values of the binding energy for the trimers Be3 and Mg3 are very close to the best estimations in Ref. [18]. 

No experimental geometry exists for the methanol dimmer so the comparison is made between the MP2/B and MM4 calculations (see Table 9.3). The MM4 results show both geometries and binding energies that seem reasonable. 

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