Convergence and efficiency of the valence bond self-consistent field method

Lenthe, Joop H. van; Verbeek, Jacob; Pulay, Péter

doi:10.1080/00268979100101841

Cited by 47 publications

(39 citation statements)

References 24 publications

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“…Table 1 reports some dissociation energies for SF*, as calculated at two different VB levels and in various basis sets. The difference between the VBSCF [20] and BOVB levels is that the latter includes dynamic electron correlation, whereas the former does not. It can be seen that VBSCF yields much too small dissociation energies, actually close to zero, whereas BOVB provides values some 20 kcal mol À1 larger, showing the paramount importance of dynamic correlation in the bonding mechanism.…”

Section: Resultsmentioning

confidence: 99%

“…There are several computational approaches for VB theory at the ab initio level. [19] In the VB self-consistent-field (VBSCF) procedure, [20] both the VB orbitals and structural coefficients are optimized simultaneously to minimize the total energy. The BOVB [18] method improves the accuracy of VBSCF without increasing the number of VB structures F K .…”

Section: Methods Sectionmentioning

confidence: 99%

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A Valence Bond Model for Electron‐Rich Hypervalent Species: Application to SF_n (n=1, 2, 4), PF₅, and ClF₃

Braı̈da

Ribeyre

Hiberty

2014

Chemistry A European J

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Some typical hypervalent molecules, SF4 , PF5 , and ClF3 , as well as precursors SF ((4) Σ(-) state) and SF2 ((3) B1 state), are studied by means of the breathing-orbital valence bond (BOVB) method, chosen for its capability of combining compactness with accuracy of energetics. A unique feature of this study is that for the first time, the method used to gain insight into the bonding modes is the same as that used to calculate the bonding energies, so as to guarantee that the qualitative picture obtained captures the essential physics of the bonding system. The (4) Σ(-) state of SF is shown to be bonded by a three-electron σ bond assisted by strong π back-donation of dynamic nature. The linear (3) B1 state of SF2 , as well as the ground states of SF4 , PF5 and ClF3 , are described in terms of four VB structures that all have significant weights in the range 0.17-0.31, with exceptionally large resonance energies arising from their mixing. It is concluded that the bonding mode of these hypervalent species and isoelectronic ones complies with Coulson's version of the Rundle-Pimentel model, but assisted by charge-shift bonding. The conditions for hypervalence to occur are stated.

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Section: Resultsmentioning

confidence: 99%

Section: Methods Sectionmentioning

confidence: 99%

A Valence Bond Model for Electron‐Rich Hypervalent Species: Application to SF_n (n=1, 2, 4), PF₅, and ClF₃

Braı̈da

Ribeyre

Hiberty

2014

Chemistry A European J

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“…[37] There are several computationala pproaches for the VB theory at the ab initio level within the classical VB formalism. [27a] In this study we have used the VB self-consistent-field (VBSCF) procedure, [38] where both the VB orbitals and structural coefficients are optimized simultaneouslyt om inimize the total energy.T he VBSCF calculations were carriedo ut with the Xiamenvalence bond (XMVB) program. [39] Some time ago,S avin proposed to analyze aw avefunction by looking at the distribution of probabilitiest of ind ag iven number n of electrons in some regions W of the real space R 3 and all other NÀn electrons outside of this domain [Eq.…”

Section: Methodsmentioning

confidence: 99%

Bonding in Heavier Group 14 Zero‐Valent Complexes—A Combined Maximum Probability Domain and Valence Bond Theory Approach

Turek

Braı̈da

Proft

2017

Chemistry A European J

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The bonding in heavier Group 14 zero-valent complexes of a general formula L E (E=Si-Pb; L=phosphine, N-heterocyclic and acyclic carbene, cyclic tetrylene and carbon monoxide) is probed by combining valence bond (VB) theory and maximum probability domain (MPD) approaches. All studied complexes are initially evaluated on the basis of the structural parameters and the shape of frontier orbitals revealing a bent structural motif and the presence of two lone pairs at the central E atom. For the VB calculations three resonance structures are suggested, representing the "ylidone", "ylidene" and "bent allene" structures, respectively. The influence of both ligands and central atoms on the bonding situation is clearly expressed in different weights of the resonance structures for the particular complexes. In general, the bonding in the studied E compounds, the tetrylones, is best described as a resonating combination of "ylidone" and "ylidene" structures with a minor contribution of the "bent allene" structure. Moreover, the VB calculations allow for a straightforward assessment of the π-backbonding (E→L) stabilization energy. The validity of the suggested resonance model is further confirmed by the complementary MPD calculations focusing on the E lone pair region as well as the E-L bonding region. Likewise, the MPD method reveals a strong influence of the σ-donating and π-accepting properties of the ligand. In particular, either one single domain or two symmetrical domains are found in the lone pair region of the central atom, supporting the predominance of either the "ylidene" or "ylidone" structures having one or two lone pairs at the central atom, respectively. Furthermore, the calculated average populations in the lone pair MPDs correlate very well with the natural bond orbital (NBO) populations, and can be related to the average number of electrons that is backdonated to the ligands.

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“…The valence bond self consistent field (VBSCF) has been devised by van Lenthe and Balint-Kurti, 79,80 and was further modified by van Lenthe, 111,112 who also developed an efficient implementation. 24 Basically, the VBSCF method is a multi-configuration SCF method that allows for the use of non-orthogonal orbitals.…”

Section: Pure Vb Methods That Use Localized Orbitalsmentioning

confidence: 99%

A survey of recent developments in ab initio valence bond theory

Hiberty

Shaik

2006

J Comput Chem

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Starting from the 1980s and onwards, Valence Bond theory has been enjoying renaissance that is characterized by the development of a growing number of ab initio methods, and by many applications to chemical reactivity and to the central paradigms of chemistry. Owing the increase of computational power of modern computers and to significant advances in the methodology, valence bond theory begins to offer a sound and attractive alternative to Molecular Orbital theory. This review aims at summarizing the most important developments of ab initio valence bond methods during the last two or three decades, and is primarily devoted to a description of what the various methods can actually achieve within their specific scopes and limitations. Key available softwares are surveyed.

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Convergence and efficiency of the valence bond self-consistent field method

Cited by 47 publications

References 24 publications

A Valence Bond Model for Electron‐Rich Hypervalent Species: Application to SF_n (n=1, 2, 4), PF₅, and ClF₃

A Valence Bond Model for Electron‐Rich Hypervalent Species: Application to SF_n (n=1, 2, 4), PF₅, and ClF₃

Bonding in Heavier Group 14 Zero‐Valent Complexes—A Combined Maximum Probability Domain and Valence Bond Theory Approach

A survey of recent developments in ab initio valence bond theory

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Convergence and efficiency of the valence bond self-consistent field method

Cited by 47 publications

References 24 publications

A Valence Bond Model for Electron‐Rich Hypervalent Species: Application to SFn (n=1, 2, 4), PF5, and ClF3

A Valence Bond Model for Electron‐Rich Hypervalent Species: Application to SFn (n=1, 2, 4), PF5, and ClF3

Bonding in Heavier Group 14 Zero‐Valent Complexes—A Combined Maximum Probability Domain and Valence Bond Theory Approach

A survey of recent developments in ab initio valence bond theory

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Product

Resources

About

A Valence Bond Model for Electron‐Rich Hypervalent Species: Application to SF_n (n=1, 2, 4), PF₅, and ClF₃

A Valence Bond Model for Electron‐Rich Hypervalent Species: Application to SF_n (n=1, 2, 4), PF₅, and ClF₃