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Canonization procedure

Below, we will define a canonical procedure for constructing probabilities of blocks of arbitrary lengths consistent with a given block probability function P. The Kolmogorov consistency theorem will then allow us to use this set of finite block probabilities to define a measure on the set of infinite configurations, F. [Pg.250]

The following steps in the study of molecular mechanisms cannot claim the status of canonical procedure, being the number of applications by far smaller, and limited to prototypical examples. We shall consider here two methods, both emphasizing the role of the RC previously defined. [Pg.17]

Figure 3.15 Application of the canonical procedure to render the Is and 2s sto-ng> basis sets of Table 1.6 mutually orthogonal as is seen in the value of the overlap integral in cell G 16 compared to the value 0.4846, cell D 16 of the unmixed originals. Note that the new functions are not normalized, cells G 15 and G 17 and that multiplication by the appropriate normalization constants cells I 12 and I 13 is required. Figure 3.15 Application of the canonical procedure to render the Is and 2s sto-ng> basis sets of Table 1.6 mutually orthogonal as is seen in the value of the overlap integral in cell G 16 compared to the value 0.4846, cell D 16 of the unmixed originals. Note that the new functions are not normalized, cells G 15 and G 17 and that multiplication by the appropriate normalization constants cells I 12 and I 13 is required.
Many canonization methods have been proposed. For earlier procedures described in the chemical literature see the paper by Jochum and Gasteiger and references cited therein [143]. Randic considered a bond matrix as canonical if the minimum binary number resulted when the rows of its upper half were concatenated [241]. Hendrickson instead used the maximum number obtained from the upper half matrix [122], Kvasnicka and Pospichal prefered the maximum number obtained from the lower half matrix [170,171]. Although such an extremality requirement obviously leads to a unique numbering, this is not necessary. Rather, the goal may be achieved using one of many procedures, provided it is well-defined and leaves no room for arbitrariness. Other canonization procedures have also been developed [37,330]. [Pg.205]

Recently, the International Union of Pure and Applied Chemistry (lUPAC) has recognized the need for a canonization procedure available to every chemist and is investing a major effort into the corresponding identifier and supporting software, the lUPAC Chemical Identifier (InChl) [121]. The latest software as well as publications may be downloaded from http //www.iupac.org/inchi/. [Pg.205]

As in many other canonization procedures, our method starts by peutitioning the graph nodes into classes according to some node-in-graph invariants. The purpose of this step is to restrict the numberings to be considered from to j , where... [Pg.206]

Note that only the renumbering schemes, not the matrices are stored, as evident from the above examples. This results in a rather low memory requirement. A detailed description of the canonization procedure was given in (17,18]. [Pg.216]

Taking all this into account, consistent quantization of this gauge field theory may be achieved, e.g., by a constrained canonical procedure [138,139] or the manifestly covariant Gupta-Bleuler formalism, which employs an indefinite metric at the expense of an easy physical interpretation [140-142]. In the following the basic ideas of the canonical procedure will briefly be presented. [Pg.243]

Chesnut D A and Salsburg Z W 1963 Monte Carlo procedure for statistical mechanical calculation in a grand canonical ensemble of lattice systems J. Chem. Phys. 38 2861-75... [Pg.2280]

The excess chemiccil potential is thus determined from the average of exp[—lT (r )/fe In ensembles other than the canonical ensemble the expressions for the excess chem potential are slightly different. The ghost particle does not remain in the system and the system is unaffected by the procedure. To achieve statistically significant results m Widom insertion moves may be required. However, practical difficulties are encounte when applying the Widom insertion method to dense fluids and/or to systems contain molecules, because the proportion of insertions that give rise to low values of y f, dramatically. This is because it is difficult to find a hole of the appropriate size and sha... [Pg.459]

For computational purposes it is convenient to work with canonical MOs, i.e. those which make the matrix of Lagrange multipliers diagonal, and which are eigenfunctions of the Fock operator at convergence (eq, (3.41)). This corresponds to a specific choice of a unitary transformation of the occupied MOs. Once the SCF procedure has converged, however, we may chose other sets of orbitals by forming linear combinations of the canonical MOs. The total wave function, and thus all observable properties, are independent of such a rotation of the MOs. [Pg.227]

Storer model used in this theory enables us to describe classically the spectral collapse of the Q-branch for any strength of collisions. The theory generates the canonical relation between the width of the Raman spectrum and the rate of rotational relaxation measured by NMR or acoustic methods. At medium pressures the impact theory overlaps with the non-model perturbation theory which extends the relation to the region where the binary approximation is invalid. The employment of this relation has become a routine procedure which puts in order numerous experimental data from different methods. At low densities it permits us to estimate, roughly, the strength of collisions. [Pg.7]

A possibly more accurate value for the double bond character of the bonds in benzene (0.46) id obtained by considering all five canonical structures with weights equal to the squares of their coefficients in the wave function. There is some uncertainty aS to the significance of thfa, however, because of- the noii -orthogOnality of the wave functions for the canonical structures, and foF chemical purposes it fa sufficiently accurate to follow the simple procedure adopted above. [Pg.203]

Except for this scaling, the other procedures are the same as in the case of tunneling splitting. The canonically invariant formula for the decay rate k can be finally obtained as... [Pg.136]

Foster JM, Boys SF (1960) Canonical configurational interaction procedure. Rev Mod Phys 32 300... [Pg.171]

Let us illustrate this procedure with the grand-canonical ensemble, and take the scenario in which we desire to achieve a uniform distribution in particle number N at a given temperature. In the weights formalism, we introduce the weighting factor r/(/V) into the microstate probabilities from (3.31) so that... [Pg.94]


See other pages where Canonization procedure is mentioned: [Pg.13]    [Pg.754]    [Pg.325]    [Pg.15]    [Pg.239]    [Pg.115]    [Pg.140]    [Pg.236]    [Pg.15]    [Pg.445]    [Pg.314]    [Pg.223]    [Pg.79]    [Pg.13]    [Pg.754]    [Pg.325]    [Pg.15]    [Pg.239]    [Pg.115]    [Pg.140]    [Pg.236]    [Pg.15]    [Pg.445]    [Pg.314]    [Pg.223]    [Pg.79]    [Pg.999]    [Pg.2268]    [Pg.2340]    [Pg.414]    [Pg.70]    [Pg.312]    [Pg.514]    [Pg.768]    [Pg.161]    [Pg.201]    [Pg.114]    [Pg.191]    [Pg.139]    [Pg.140]    [Pg.148]    [Pg.167]    [Pg.119]    [Pg.81]    [Pg.100]    [Pg.108]    [Pg.109]   
See also in sourсe #XX -- [ Pg.214 , Pg.236 , Pg.238 ]




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