INDO molecular orbital calculation

Breton et al. <2002JOC6699> have reported some computational studies on a few selected derivatives of 1,2-dihydrodiazete. Warrener performed some semi-empirical intermediate neglect of differential overlap (INDO) molecular orbital calculations on unsubstituted dihydrodiazete, cis- and trans-14 <1979AJC2659>. 

INDO molecular orbital calculations of x and rj have been reported for some azoloazines (63) and for Ba(N03)2. (180) The agreement with experimental 14N NMR data is reasonable for the azoloazines. 

The geometries and esr coupling constants of the radical 3 (R = Me) and also the parent cation 3+ (Section XIII) have been compared with data from INDO molecular orbital calculations [85JCS(D)1405]. 

HyperChem currently supports one first-principle method ab initio theory), one independent-electron method (extended Hiickel theory), and eight semi-empirical SCFmethods (CNDO, INDO, MINDO/3, MNDO, AMI, PM3, ZINDO/1, and ZINDO/S). This section gives sufficient details on each method to serve as an introduction to approximate molecular orbital calculations. For further details, the original papers on each method should be consulted, as well as other research literature. References appear in the following sections. 

The 327-670 GHz EPR spectra of canthaxanthin radical cation were resolved into two principal components of the g-tensor (Konovalova et al. 1999). Spectral simulations indicated this to be the result of g-anisotropy where gn=2.0032 and gi=2.0023. This type of g-tensor is consistent with the theory for polyacene rc-radical cations (Stone 1964), which states that the difference gxx gyy decreases with increasing chain length. When gxx-gyy approaches zero, the g-tensor becomes cylindrically symmetrical with gxx=gyy=g and gzz=gn. The cylindrical symmetry for the all-trans carotenoids is not surprising because these molecules are long straight chain polyenes. This also demonstrates that the symmetrical unresolved EPR line at 9 GHz is due to a carotenoid Jt-radical cation with electron density distributed throughout the whole chain of double bonds as predicted by RHF-INDO/SP molecular orbital calculations. The lack of temperature... 

M.O. Calculations. The serai-empirical molecular orbital calculations were made using the UHF INDO model developed by Pople and co-workers (13), which incorporates the one-center exchange integral. Additionally, instead of assuming standard values for bond distances and angles, full geometry optimization at the INDO level was employed (14). Thus the results do not depend upon an arbitrary choice for the molecular geometry. 

The electronic structures of the hetero- and homobimetallic triple-deckers 11 and 12 were investigated by photoelectron spectroscopy and intermediate neglect of differential overlap (INDO) molecular orbital (MO) calculations, which revealed that the metal-borole interaction is stronger in the dimanganese system 12 than in 11, owing to better Mn-borole versus Co-borole orbital overlap.12... 

Of the Ru(IV) complexes recorded here most are mono-oxo species which, despite the strong axial distortion brought about by the terminal oxo ligand, are probably all paramagnetic. Semi-empirical molecular orbital calculations (INDO/1) for epoxidations effected by oxo-Ru(IV) complexes have been reported (a non-concerted [1 h- 2] pathway was preferred) [642], [643] and for alcohol oxidations by octahedral species containing an Ru" (0) unit [644]. The reactivity of high oxidation-state polypyridyl complexes of osmium and Ru, with particular emphasis on Ru(IV) and Os(IV) oxo species, has been reviewed [43]. 

The rates of solvolysis of 4- and 5-substituted l-(2-thienyl)ethyl p-nitrobenzoates in 80% EtOH at 25° are correlated by a p value of —6.79,265 to be compared with —5.7 for the benzenoid reaction. Using o+ values calculated by the Dewar-Grisdale approach [Eq. (2)] incorporating q parameters derived from CNDO/2 or INDO molecular orbital procedures (which give closely similar results) gives a value of p of —7.14. For the equivalent 4-substituted l-(2-furyl)ethyl systems,266 267 however, the correlation with o is poor, p being —8.5. In this case Eq. (2) yields o+ values providing a close fit to experimental determinations with a p value that is appropriate for the benzenoid reaction. 

Local density functional (LDF) quantum mechanical calculations for materials science. deMon for density functional calculations. Turbomole for Hartree-Fock and MP2 ab initio calculations. ZINDO for extended Fliickel, PPP, CNDO, and INDO semiempirical molecular orbital calculations and prediction of electronic spectra. Plane Wave for band structures of semiconductors. ESOCS for electronic structure of solids. Silicon Graphics and IBM workstation versions. 

Time and temperature dependences of the delayed fluorescence in isotopi-cally mixed naphthalene crystals have been presented for various concentrations of traps. Coherent two-photon processes in naphthalene in the strong exciton-photon counting regime have also been investigated. Excited-state spectra of 1,5-naphthyridine in several solvents support those calculated using INDO molecular orbital formalism and show the lowest excited singlet state to... 

A long-standing difficulty of most semiempirical molecular orbital calculations (HMO, EHT, PPP, CNDO, INDO, MINDO, etc.) has been the... 

Semi-empirical molecular orbital calculations using the INDO/S method have been carried out for organoscandium complexes of the general formula Cp 2ScX (X = C1, I, Me, CH2Ph, NHPh).549 The utility of electrospray mass spectrometry for the characterization of air-sensitive organolanthanides and related species has been demonstrated.550 A wide variety of lanthanide complexes, including divalent and trivalent compounds, neutral and... 

Aniline and the fluoroanilines exhibit, 4N contact shifts in the presence of (pentane-2,4-dionato) nickel(II). By comparing the shifts with spin densities calculated by the INDO molecular orbital procedure a structure is proposed for the complexes formed in solution. (137) Contact shifts have also been reported from the 14N spectra of some cobalt(II) nitrate complexes. (138) In the case of [Co(H20)5N03] the chemical shift of the nitrate ligand is reported to be 2360 100 ppm to high frequency of the free nitrate ion. (222)... 

One of the most successful methods of calculating nuclear spin coupling constants involves application of SCF perturbation theory and use of the INDO molecular orbital (MO) approximations. (8-17) In most theoretical studies aAB and bAB are taken as empirical parameters, adjusted to give best agreement between theory and experiment. Values of the individual integrals calculated from Slater exponents (14) are given in Table I. 

For MnCp2(3d ) esr and photo-electron measurements ) have established the existence of an equilibrium between the high spin A g and low spin states, which at the same time was endorsed by INDO molecular orbital results ). The values calculated for the metal-ring separations were in essential agreement with a later... 

True Hiickel molecular orbital calculations, among other limitations, only address TT-electrons. All atom, semiempirical calculations that include both n- and a-electrons were developed originally by Pople and coworkers [17] implementing the method of complete neglect of differential overlap (CNDO), followed by the increasingly rigorous method of intermediate neglect of differential overlap (INDO) [18]. 

R. D. Brown, B. H. James, and M. F. O Dvvycr, Tbeor. Chim. Acta, 17, 264 (1970). Molecular Orbital Calculations on Transition Element Compounds. W. T. A. M. V an der Lugt, hit. J. Quantum Chem., 6, 859 (1972). Molecular-Orbital Calculations on Transition-Metal Complexes, Charge-Transfer Spectra, and the Sequence of Metal and Ligand Orbitals. J. J. Kaufman and R. Predney, hit. J. Quantum Chem., Quantum Chem. Symp., 6, 231 (1972). Extension of INDO Formalism to d Orbitals and Parameters for Second-Row Atoms. 

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