Charge distribution and chemical effects. IV. Criterion for selecting a theoretical method for the study of molecular properties involving charges

Fliszár, Sándor; Kean, G.; Macaulay, R.

doi:10.1021/ja00821a001

Cited by 37 publications

(28 citation statements)

References 2 publications

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“…4 The present work concludes eventually that eqs. [5] and [6] are, indeed, satisfactory in conjunction with eq. [2] provided that charge analyses are carried out after configuration interaction involving sufficiently large optimized basis sets.…”

Section: Introductionsupporting

confidence: 56%

“…[5] and [6]. It has been shown (2, 6) that the following relationship holds: Accordingly, the connection with eqs.…”

Section: Relative Ordering Of Net Chargesmentioning

confidence: 88%

“…[2]. Indeed, when deduced from SCF (Hartree Fock) wave functions, this analysis yields charge results which are strongly basis set dependent (3,5), both as regards their relative ordering and their magnitude.…”

Section: Introductionmentioning

confidence: 87%

“…Moreover, the general formulas of Table 1 apply equally well to results deduced from eqs. [5] and [6].…”

Section: Relative Ordering Of Net Chargesmentioning

confidence: 99%

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Charge distributions and chemical effects. XXXVI. Charge analysis involving configuration interaction: application to alkanes

Mijoule¹,

Odiot²,

Fliszár³

1985

Can. J. Chem.

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An analysis of atomic charges is presented for simple alkanes. Basically, Mulliken's scheme is followed, except for the partitioning of CH overlap populations. This achieves a relative ordering of atomic charges which is independent of the basis sets used in nb inirio calculations. The absolute magnitude of atomic charges, however, is basis set dependent. Extensive geometry and scale factor optimizations yield the following results (in lo-' e units) for the carbon net charge in ethane: 69.4 (STO-3G), 55.1 (STO-3G + CI), 42.8 (4-31G). and 37.8 (4-31G + CI). It appears that charge analyses converge toward the empirical result, 35.1 X lo-? e, provided they are carried out after configuration interaction involving reasonably large optimized basis sets. IntroductionThe concept of atomic charge is popular in chemistry. The quantity which is referred to in most cases is the net charge qk = Z, -N(k), where Z, is the nuclear charge of center k and N(k) the number of electrons assigned to it. Numerous studies have dealt with the problem of charge partitioning, which are well reviewed (1): the disturbing fact is that charge results vary widely, depending on the methods involved in their calculation.The question asked here is one concerning a realistic, physically meaningful partitioning which will not defeat itself in applications and comparisons involving experimental results. Though limited in scope (as we are primarily discussing saturated hydrocarbons), this work attempts to show what level of calculation fulfills the requirements for achieving this goal, a task involving some kind of experimental assessment of the theoretical results.With this in mind, advantage is taken from earlier studies (2, 3) indicating that the individual bond energies of ground-state molecules are (to a good approximation) linearly dependent on the charges of the bond-forming atoms,' i.e.,

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Section: Introductionsupporting

confidence: 56%

“…[5] and [6]. It has been shown (2, 6) that the following relationship holds: Accordingly, the connection with eqs.…”

Section: Relative Ordering Of Net Chargesmentioning

confidence: 88%

Section: Introductionmentioning

confidence: 87%

“…Moreover, the general formulas of Table 1 apply equally well to results deduced from eqs. [5] and [6].…”

Section: Relative Ordering Of Net Chargesmentioning

confidence: 99%

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Charge distributions and chemical effects. XXXVI. Charge analysis involving configuration interaction: application to alkanes

Mijoule¹,

Odiot²,

Fliszár³

1985

Can. J. Chem.

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“…Can The real difficulty rests with the "true" values of m and d6ca/dq, because atomic charges calculated from Mulliken's sdheme are strongly basis set dependent, particularly as regards u charges. Charge separations are invariably larger when increasingly larger basis sets are used in ab initio calculations, to the point that unrealistic results are obtained (6). Charge analyses carried out at the STO-3G level (5) suggest a value of -250 ppm/e for the d6ca/dqn slope, which is probably also a result of slightly overestimated n charges.…”

Section: Introductionmentioning

confidence: 99%

Charge distributions and chemical effects. XXXI. Molecular energies of ethylenic compounds

Béraldin¹,

Fliszár²

1983

Can. J. Chem.

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The energy formula describing bond contributions in terms of the charges carried by the bond-forming atoms is applied to ethylenic compounds. It is shown in what manner σ and π electrons can be treated within the framework of the bond energy theory giving the atomization energy of the vibrationless molecule at 0 K. Proper consideration of zero-point and thermal vibrational energies leads to standard enthalpies of formation. These calculations, which are carried out on the basis of, 13C nuclear magnetic resonance spectra, agree with their experimental counterparts, within experimental uncertainties (~0.3 kcal mol−1 average deviation).

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Electronic structure and ¹³ C Nmr

Nelson

Williams

1976

Progress in Physical Organic Chemistry

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Charge distribution and chemical effects. IV. Criterion for selecting a theoretical method for the study of molecular properties involving charges

Cited by 37 publications

References 2 publications

Charge distributions and chemical effects. XXXVI. Charge analysis involving configuration interaction: application to alkanes

Charge distributions and chemical effects. XXXVI. Charge analysis involving configuration interaction: application to alkanes

Charge distributions and chemical effects. XXXI. Molecular energies of ethylenic compounds

Electronic structure and ¹³ C Nmr

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Charge distribution and chemical effects. IV. Criterion for selecting a theoretical method for the study of molecular properties involving charges

Cited by 37 publications

References 2 publications

Charge distributions and chemical effects. XXXVI. Charge analysis involving configuration interaction: application to alkanes

Charge distributions and chemical effects. XXXVI. Charge analysis involving configuration interaction: application to alkanes

Charge distributions and chemical effects. XXXI. Molecular energies of ethylenic compounds

Electronic structure and 13 C Nmr

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Electronic structure and ¹³ C Nmr