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Modified neglect

Highest occupied molecular orbital Intermediate neglect of differential overlap Linear combination of atomic orbitals Local density approximation Local spin density functional theory Lowest unoccupied molecular orbital Many-body perturbation theory Modified INDO version 3 Modified neglect of diatomic overlap Molecular orbital Moller-Plesset... [Pg.124]

MNDO (modified neglect of diatomic overlap) a semiempirical method model a simple way of describing something that is actually more complex than the model... [Pg.366]

The modified neglect of differential overlap (MNDO) model should probably come next MNDO is like INDO except that MNDO treats the diatomic two-electron integrals more accurately. It retains all two-electron integrals involving monatomic differential overlap, and the paper to read is probably ... [Pg.152]

The core-core repulsion of the Modified Neglect of Diatomic Overlap (MNDO) modeP has the form ... [Pg.86]

The systems discussed in this chapter give some examples using different theoretical models for the interpretation of, primarily, UPS valence band data, both for pristine and doped systems as well as for the initial stages of interface formation between metals and conjugated systems. Among the various methods used in the examples are the following semiempirical Hartree-Fock methods such as the Modified Neglect of Diatomic Overlap (MNDO) [31, 32) and Austin Model 1 (AMI) [33] the non-empirical Valence Effective Hamiltonian (VEH) pseudopotential method [3, 34J and ab initio Hartree-Fock techniques. [Pg.74]

Modified neglect of diatomic overlap (MNDO) calculations can support the structures assigned to certain of these fused tricyclic systems, such as 401, where confirmatory X-ray crystallographic data are lacking <1983JCM128>. [Pg.849]

A theoretical study of degenerate Boulton-Katritzky rearrangements concerning the anions of the 3-hydroxyimi-nomethyl-l,2,5-oxadiazole has been carried out by using semi-empirical modified neglect of diatomic overlap (MNDO) and ab initio Hartree-Fock procedures. Different transition structures and reactive pathways were obtained in the two cases. Semi-empirical treatment shows asymmetrical transition states and nonconcerted processes via symmetrical intermediates. By contrast, ab initio procedures describe concerted and synchronous processes involving symmetrically located transition states <1998JMT(452)67>. [Pg.318]

Various theoretical methods (self-consistent field molecular orbital (SCF-MO) modified neglect of diatomic overlap (MNDO), complete neglect of differential overlap (CNDO/2), intermediate neglect of differential overlap/screened approximation (INDO/S), and STO-3G ab initio) have been used to calculate the electron distribution, structural parameters, dipole moments, ionization potentials, and data relating to ultraviolet (UV), nuclear magnetic resonance (NMR), nuclear quadrupole resonance (NQR), photoelectron (PE), and microwave spectra of 1,3,4-oxadiazole and its derivatives <1984CHEC(6)427, 1996CHEC-II(4)268>. [Pg.398]

In a seminal theoretical paper, we showed that, at the Modified Neglect of Differential Overlap (MNDO) level, phenylnitrenium ions 17 as well as NH2, PH2,... [Pg.38]

Modified Neglect of Diatomic Overlap -type Semiempirical Methods... [Pg.31]

This new model f6), called MNDO for Modified Neglect of Diatomic Overlap, was published oy Dewar and Thiel in 1977. With MNDO the average errors (5) for the same survey of C, H, N and O molecules decreased to 6.3 kcal/mol for AHf, 0.014 A for bond lengths and 0.48 eV for ionization potentials. Since MNDO used only atomic parameters, parameterization of MNDO to include additional elements was much easier than with MINDO/3, and, over the next eight years, parameters were optimized for 16 elements in addition to C, H, N and O. [Pg.33]

The bicyclo[2.2.2]octane-l,4-diyl dication, 61, and its tricyclopropane derivative, 62, could not be prepared under stable ion conditions even though they were attempted under various reaction conditions. The possible existence of these carbodications was supported by Modified Neglect of Differential Overlap (MNDO) calculations. [Pg.231]


See other pages where Modified neglect is mentioned: [Pg.116]    [Pg.279]    [Pg.284]    [Pg.175]    [Pg.88]    [Pg.12]    [Pg.1]    [Pg.34]    [Pg.1]    [Pg.107]    [Pg.22]    [Pg.116]    [Pg.101]    [Pg.604]    [Pg.613]    [Pg.1071]    [Pg.1010]    [Pg.630]    [Pg.1435]    [Pg.1014]    [Pg.306]    [Pg.1418]    [Pg.1072]    [Pg.1549]   


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MINDO (modified intermediate neglect

MINDO/3 (Modified Intermediate Neglect molecular orbital method

MNDO (modified neglect of diatomic

MNDO (modified neglect of differential

Modified Intermediate Neglect of Differential

Modified Intermediate Neglect of Differential Overlap

Modified Intermediate Neglect of Differential Overlap (MINDO)

Modified Intermediate Neglect of Differential Overlap method

Modified Neglect of Diatomic Overlap

Modified Neglect of Diatomic Overlap MNDO)

Modified Neglect of Diatomic Overlap MNDO) method

Modified Neglect of Diatomic Overlap Parametric Method Number 3

Modified Neglect of Diatomic Overlap method

Modified Neglect of Differential

Modified Neglect of Differential Overlap

Modified Neglect of Differential Overlap MNDO) model

Modified Neglect of Differential Overlap method

Modified intermediate neglect

Modified intermediate neglect differential overlap

Modified intermediate neglect differential overlap model

Modified neglect of diatomic

Modified neglect of diatomic differential

Modified neglect of diatomic differential overlap

Modified neglect of differential overlap MNDO)

Neglect

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