INDO/CIS

Duijnen, P.Th. van and Netzel T.L., Explicit Solvent DRF INDOs/CIS Computations of Charge Transfer State Energetics in a Pyrenyldeoxyuridine Nucleoside Model. J.Phys. Chem. A (2006) 110 2204-2213. 

Good test cases would be the solvent effects on the UV-vis absorption spectra of formaldehyde and acetone that have been the subject of innumerous theoretical studies. Innovative theoretical methods have been applied to formaldehyde (see also the compilation of results in [20,32,113,114,115,116]). Unfortunately the experimental result for formaldehyde in water is not clear because of chemical problems mostly associated to the aggregation and formation of oligomers. Therefore a better test case is the UV-vis spectra of acetone, because reliable experimental solvent shifts and several theoretical results are available (see the compilation of results in [117]). The Stokes shift of the n-rr transition of acetone has been critically discussed by Ohrn and Karlstrom [118], Grozema and van Duijnen [17] studied the solvatochromic shift of the absorption band of acetone in as much as eight different solvents. Acetone is known to shift the maximum of the n-rr band by 1500-1700 cm 1 when immersed in water [119,120,121], Using the conventional HF/6-31 G(d) point charges, Coutinho and Canuto [54] simulated acetone in water and performed INDO/CIS... 

Using the atomic charges obtained from a CHELPG fit of the isolated molecule in the MC simulation results in calculated subsequent INDO/CIS solvatochromic shifts of approximately 990 cm-1 for the n-rr band and -950cm-1 for the tt-tt. These values are disappointingly small compared to the experimental values of 2000 and -1600 cm-1, respectively. Using, in turn, the implicit polarization obtained with the HF/6-31 G(d) we calculated a solvent shift of approximately 1400 cm-1 for the n—tt band and -1200 cm-1 for the tt-tt, corresponding to an improved picture... 

Zhou. Y.-F., Wang, X.-M, Zhao, X., Jiang, M,-H, A quantum-chemical INDO/CI method for calculating two-photon cross sections. J. Phys, Chem. Sol. 62, 1075—1079 (2001)... 

An in-depth review on lanthanide containing molecules calculations has been given by Dolg and Stoll [92]. Several studies carried out on CeO and YbO by different groups are reported in the following. The excited states of CeO have been calculated at different levels of theory, namely INDO/CIS by Kotzian etal[ A ] and ECPs SCF/CISD/CIPSO calculations by Dolg etal[ 42]. The vertical transition energies Tg are presented in Table 5. 

The geometries, electronic structures and electronic spectra of stilbene derivatives and chromophores based on dithienothiophenes are systematically studied by AMI and INDO/CI method. On the basis of correct UV-Vis spectra, the position and strength of the two-photon absorption can be predicted (2001MI1). 

Table 11.1.5. The INDO/CI calculated solvatochromic shifts Av (from the gas phase to cyclohexane) of some aromatic compounds and the respective experimental data in low polarity solvents (cm )° ...

The equation [11.1.130] has been used within the semiempirical quantum-chemical INDO/CI formalism to calculate the solvent shifts of some aromatic compounds in cyclohexane. The results compare favorably with the experimental data for some nonpolar solvents (cf Table 11.1.5). 

Micron- and submicron-scale lateral structures of optically nonlinear organic films comprised of substituted trons-stilbene derivatives (Ri = OCH3, R2 = CN) was characterized [45]. Second harmonic generation (SHG), optical microscopy, and atomic force microscopy (AFM) were used in this investigation. The third-order nonlinear optical properties and two-photon absorption ofdifferent types of stilbene derivatives (D-tt-D, A-7t-A, D-7t-A) were investigated [46]. Using the INDO/CI method, the UV-vis spectra were explored and the position and strength of the two-photon absorption were predicted by sum-over-states expression. Relationships of the structures, spectra, and nonlinear optical properties have been examined. Two-photon absorption spectra (650-1000 nm) of a series of asymmetrically substituted stilbenoid chromophores... 

Onsager s SCRF is the simplest method for taking dielectric medium effects into account and more accurate approaches have been developed such as polarizable continuum modes, " continuum dielectric solvation models, - explicit-solvent dynamic-dielectric screening model, - and conductor-like screening model (COSMO). Extensive refinements of the SCRF method (spherical, elliptical, multicavity models) in conjunction with INDO/CIS were introduced by Zerner and co-workers ° as well. 

There are several other semi-empirical methods such as the relativistic extended Hiickel method formulated by Pyykko and co-workers. The Dirac-Slater multiple Xa method (Case 1982) has also been employed to include relativistic effects approximately. Zerner and co-workers use the INDO/CI method to study lathanide compounds. We will discuss these in section 3.2. 

INDO/CI calculations. ) Trans to c-orbital. ) Cis to (T-orbital. ) Presumably trans to [Pg.526]

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