Cioslowski

The resulting similarity measures are overlap-like Sa b = J Pxi ) / B(r) Coulomblike, etc. The Carbo similarity coefficient is obtained after geometric-mean normalization Sa,b/ /Sa,a Sb,b (cosine), while the Hodgkin-Richards similarity coefficient uses arithmetic-mean normalization Sa,b/0-5 (Saa+ b b) (Dice). The Cioslowski [18] similarity measure NOEL - Number of Overlapping Electrons (Eq. (10)) - uses reduced first-order density matrices (one-matrices) rather than density functions to characterize A and B. No normalization is necessary, since NOEL has a direct interpretation, at the Hartree-Fodt level of theory. 

CBS extrapolation 155, 278 CBS methods 10, 96, 155 cost vs. G2 methods 159 CBS-4 method 155 CBS-Q method 155 CCSD keywords 114 CH bond dissociation 186 charge xxxv, xlii, 15, 286 predicted atomic li charge distribution 20 Cheeseman 53 chlorine (atomic) 137, 159 chlorobenzene 165 chromium hexacarbonyl 52 Cioslowski 198 CIS keyword... 

Such a matrix is not independent on the coordinate system, but the trace is. Cioslowski has proposed a definition of atomic charges as one-third of the trace over the APT, denoted Generalized Atomic Polar Tensor (GAPT) charges.The charge on atom A is defined as... 

Cioslowski J (1993) Int J Quantum Chem Quantum Chem Symp 27 309... 

UB3LYP theory predicts four minima of Sg which possess Cj, Cjhy O2 d C2 symmetries. At the UMP2 level of theory, no stationary point corresponding to the C2 minimum can be located and two new local minima with and D2 symmetries appear. The Sg conformers are found to be very prone to pseudorotation and are predicted to interconvert readily. For this reason, Cioslowski et al. refer to Sg as a fluxional species [93]. Interestingly, they found that the structures corresponding to local minima are not directly interconvertible. 

Theoretical calculations by Mixon and Cioslowski (1991) suggested that a push-pull substituted ethane (H2N)3C—C(N02)3 exists as an ion pair (H2N)3C C(N02)3. Recently, a similar hexamethylguanidinium-... 

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