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Distinct row table

To describe the computation of the coupling coefficients with the formalism of the unitary group approach, the distinct row table (DRT) and its graphical... [Pg.99]

ANO = atomic natural orbital CSF = configuration state function DRT = distinct row table FCI = full configuration interaction GUGA = graphical unitary group approach PNO = pseudonatural orbital or pair natural orbital UGA =... [Pg.485]

A computer program requires the Shavitt graph in a digital form, the so-called distinct row table (DRT). As a matter of fact, the first achievement in the exploitation of the UGA was the Paldus tableaux for individual CSFs, The distinct rows from these were collected in the ORT and the latter was then given diagrammatic expression by Shavitt and called after him the Shavitt graph. [Pg.491]

In the case of RG I we have a fixed assignment of the chemical elements to the rows/columns of the BE-matrix B. Thus it is even possible to use different transition tables for a given chemical element in the distinct rows/columns. [Pg.143]

Upfield shifts of multiply heterosubstituted carbon atoms are well known in the 13C NMR literature. Some representative examples are shown in Figure 9 and Table 16, where the actual l3C chemical shifts and individual a-SCSs, respectively, for each newly introduced substituent in methane derivatives are compiled. The ICSs can be calculated by subtracting any a-SCS from its respective predecessor within a given row in Table 16. The general trend is toward a distinct decrease of a-SCS with progressive substitution that is, all the ICSs are negative. [Pg.272]

Popular pseudopotentials in modem use include those of Hay and Wadt (sometimes also called the Los Alamos National Laboratory (or LANE) ECPs Hay and Wadt 1985), those of Stevens et al. (1992), and the Stuttgart-Dresden pseudopotentials developed by Dolg and co-workers (2002). The Hay-Wadt ECPs are non-relativistic for the first row of transition metals while most others are not as relativistic effects are usually quite small for this region of the periodic table, the distinction is not particularly important. Lovallo and Klobukowski (2003) have recently provided additional sets of both relativistic and non-relativistic ECPs for these metals. Eor the p block elements. Check et al. (2001) have optimized polarization and diffuse functions to be used in conjunction with the LANE double-t basis set. [Pg.179]

The 2nd catalyst bed worksheet area is set up much like the 1st (with a different input gas temperature, Table 18.1). The distinctive difference is that the input quantities in row 8 are 1st catalyst bed exit (intercept) gas quantities from Table S.l cells B38 through B42. The latter are automatically copied into the 2nd catalyst bed area by the instructions ... [Pg.363]

Manganese(II) compounds are quite labile the metal shows distinct class (a) character 7 and its ionic radius (defined by the M—H20 distances in Table 1) is large compared with the other first row transition metals. These lead to distinct parallels with magnesium(II) rather than the latter, although there are also significant parallels with octahedral high spin nickel(II). [Pg.3]

Another important point of distinction with E is that the three-body term is evaluated with all interactions computed in the precise geometry, internal as well as intermolecular, of the trimer. In contrast, E permits relaxation of the geometry of each entity, monomer, dimer, or trimer. The appropriate row of Table 5.24 reports these three-body terms for the 1 2 complexes, which are each reduced relative to This reduction is... [Pg.275]

The geometric features of the binary complexes are listed in Table 5.28, along with the 1 2 complex in the last two rows. The expected contraction of the O—F distance as the second HF molecule is added is immediately apparent. This contraction amounts to 0.10 A at the SCF level, less than that in the HjN—HF- HF complex where the shrinkage was 0.13 A. Correlation has little influence on the H-bond reduction the MP2 contraction is 0.11 A. From the perspective of adding the proton acceptor molecule to the FIF dimer, R(F"F) is reduced by 0.12 A for both H2O and NH3, at the SCF level. The distinction between the latter two molecules is perhaps most clearly seen in the bond length of the inner HF molecule, ij. This bond stretches by 0.017 A when the outer HF molecule is added to HjN- HF, but by only 0.009 A if H N is replaced by HjO. Note, however, that when correlation is added, this stretching doubles. [Pg.279]

A systematic comparison of various symmetric anionic complexes provides a solid basis for comparison, The data listed in Table 6,8 illustrate the rapid decline in binding energy as the electronegativity of the atoms diminishes, or as one passes from first to second-row atoms. Concomitant with this weakening of the interaction is the lengthening of the H-bond. In a number of cases, there is a fine distinction as to whether the H-bond is centrosymmet-... [Pg.310]

With only s- and p-functions included, the MNDO/AM1/PM3 methods are unable to treat a large part of the periodic table. Furthermore, from ab initio calculations it is known that d-orbitals significantly improve the results for compounds involving second row elements, especially hypervalent species. The main problem in extending the NDDO formalism to include d-orbitals is the significant increase in distinct two-electron Jntegrals which ultimately must be assigned suitable values. For an sp-basis there are... [Pg.52]

The periodic table has columns and rows of varying sizes. The reason behind the table s odd shape becomes clear if it is divided into sections, or blocks, representing the atom s energy sublevel being filled with valence electrons. Because there are four different energy sublevels (s, p, d, and f), the periodic table is divided into four distinct blocks, as shown in Figure 6-10. [Pg.160]

One more complicating factor must now be considered the effect of duration of exposure. Consider the data shown in Table 20. In each of the rows, the Ct product = 100 mg min m-3. In the rows (c), (d) and (e), one might feel reasonably confident that the mortality likely to occur would be about 50%, i.e. an LCtso exposure. At the outer rows, one becomes distinctly less confident and it is unlikely that continuous exposure of a person to 0.0001 mg m 3 GB for 1.9 years would have the same effect as exposure to 10 mg m 3 for 10 min. Interestingly, the US permissible exposure limit for GB (expressed as an 8-h time-weighted average (TWA), is 0.0001 mg m 3 such an exposure, on a daily, life-long basis, would be regarded as safe. [Pg.55]


See other pages where Distinct row table is mentioned: [Pg.67]    [Pg.132]    [Pg.409]    [Pg.162]    [Pg.53]    [Pg.67]    [Pg.132]    [Pg.409]    [Pg.162]    [Pg.53]    [Pg.89]    [Pg.6]    [Pg.170]    [Pg.718]    [Pg.170]    [Pg.82]    [Pg.33]    [Pg.306]    [Pg.57]    [Pg.494]    [Pg.854]    [Pg.542]    [Pg.1317]    [Pg.360]    [Pg.93]    [Pg.1317]    [Pg.161]    [Pg.17]    [Pg.62]    [Pg.854]    [Pg.89]    [Pg.334]    [Pg.841]    [Pg.432]    [Pg.204]    [Pg.872]    [Pg.43]    [Pg.316]    [Pg.631]    [Pg.161]   
See also in sourсe #XX -- [ Pg.99 , Pg.409 ]




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