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Ordering, canonical

Program RW INTS This program is designed to read the one- and two- electron AO integrals (in Dirac <12 12> convention) from use r input and put them out to disk in canonical order. There are no memory limitations associated with program RW INTS. [Pg.647]

Suppose a r-electron operator to be written as S2(r), with the r-dimensional vector r representing the coordinates of the canonically ordered r (matrix element between two Slater determinants can te written as ... [Pg.237]

The renormalization factors can be chosen such that the limit -+ 0 for exists for all dimensions d < 4, the corrections being of canonical order 2/(tir r) ... [Pg.185]

The notion of canonical order needs some explanation. A priori in jtt-tli order of perturbation theory in u the leading neglected term is found to be proportional to... [Pg.186]

Following a canonical order to get molecular wavefunctions, we introduce here the Hartree-Fock (HF) level of the two-step approach described above. In this framework we have to define the Fock operator for our model. We adopt here an expansion of this operator over a finite basis set and thus all the operators are given in terms of their matrices in such a basis. The Fock matrix reads ... [Pg.85]

Denotations and connotations of the term "polymer" and its associated building block, termed "monomer", are probed. The nomenclature previously developed in order to canonically name finite length molecules is extended so as to apply to unlimited repeats of the monomer. A system of taxonomy based on dimension underlies the choice of canonical ordering of "polymers", as well as that aggregation of atoms which lacks the "regularity" to meet the proposed limitation to the definition of the term "polymer" (herein called "multimer") is introduced. The extension from Cartesian nomenclature to spherical nomenclature introduced in Chapter 6 is further developed for "dendritic" molecules. [Pg.269]

For the above limited field of polymers, as well as the shift in focus from source-based to structure-based, further elucidation is achieved when one is compelled to assign a canonical name that is capable of differentiating between "similar" polymers. One of the fall-outs of this is the establishment of a canonical ordering of the atoms in the... [Pg.330]

Such an index may be automatically assigned by a canonical ordering procedure such as the algorithm CANON [32]. [Pg.213]

Finally, the canonical ordering is performed on the basis of P, values and in the case of equivalence, according to the values of the matrix. Atoms with the greatest values are assigned the smallest numerical labels in the canonical ordering, such atoms being closest to the graph centre. [Pg.37]

The sum N = I + J + K is the order of the moment to which a given element belongs. The moment polytensor, M, is the single index array of the usual moment elements in canonical order from the zeroth moment (charge) to the first (dipole), second (quadrupole), and so on, to any desired level of termination ... [Pg.24]

Elk, S.B. (1990) A canonical ordering of polybenzenes and polymantanes using a prime number factorization technique./. Math. Chem., 4, 55-68. [Pg.1031]

Figure 4.5. The limiting mechanisms of three-step hydride transfer and one-step hydride transfer, the former in the canonical order of Powell and Bruice [37], for the overall reduction by NAD(P)H of hydride-acceptor molecules. The operative distinctions are that (a) there are radical/radical-ion intermediates in the... Figure 4.5. The limiting mechanisms of three-step hydride transfer and one-step hydride transfer, the former in the canonical order of Powell and Bruice [37], for the overall reduction by NAD(P)H of hydride-acceptor molecules. The operative distinctions are that (a) there are radical/radical-ion intermediates in the...
The column structure.id is a unique integer relating the structure, sdf and property tables. The sdf.molfile column contains the molfile for each structure as defined by the vendor. The structure.name and structure.cansmiles columns contain the name and canonical smiles parsed and computed from the molfile. The structure.coord column will contain an array of atomic coordinates. The structure, atom column will contain an array of atom numbers from the file in canonical order to correspond to the atom order in the canonical SMILES. The OpenBabel/plpythonu extension functions molfile mol and molfile properties will be used to parse the vendor SDF molfiles and populate these tables. The molfile column of the sdf table is first populated from the SDF file, using the following perl script. [Pg.126]


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See also in sourсe #XX -- [ Pg.48 , Pg.58 ]




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Atomic coordinates canonical order

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