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Reference state field

Similar corrsideratiorts have to be applied to electric state variables. We have to distinguish the spatial frame or present state electric field f and the material frame or reference state field E, which are related by... [Pg.104]

Thus the matrix elements of the electron propagator are related to field operator products arising from the superoperator resolvent, El — H), that are evaluated with respect to N). In this sense, electron binding energies and DOs are properties of the reference state. [Pg.37]

It is also possible to employ highly correlated reference states as an alternative to methods that employ Hartree-Fock orbitals. Multiconfigu-rational, spin-tensor, electron propagator theory adopts multiconfigura-tional, self-consistent-field reference states [37], Perturbative corrections to these reference states have been introduced recently [38],... [Pg.140]

In the self-consistent field linear response method [25,46,48] also known as random phase approximation (RPA) [49] or first order polarization propagator approximation [25,46], which is equivalent to the coupled Hartree-Fock theory [50], the reference state is approximated by the Hartree-Fock self-consistent field wavefunction < scf) and the set of operators /i j consists of single excitation and de-excitation operators with respect to orbital rotation operators [51],... [Pg.474]

In this expression, K is the thermodynamic equilibrium constant, which can be multiplied by Na/p (with Na equal to Avogadro s number) to obtain the commonly used equilibrium constants based on the molar bulk concentration reference state. It is important to note that the exponential term in the right-hand side of Equations 2.20 and 2.21 is an activity coefficient term. This term depends on the interaction field n z), which is nonlocal and therefore it couples with all the interactions and chemical equilibria in all regions of the film. [Pg.94]

In the field of environmental organic chemistry, the most common reference states used include (1) the pure liquid state, when we are concerned with phase transfer processes (2) the infinite dilution state, when we are dealing with reactions of... [Pg.77]

The reference state is the composition-weighted linear combination of pure A and B components. This approximation neglects vibrational entropy. Higher-order mean-field approximations to configurational entropy, known as the cluster-variation method, are known [5, 6]. [Pg.425]

This takes us halfway. The entire procedure has to be repeated for the second phase a, integrating along some path parameterized (in general) by some other field X running between the macrostate a,c and some other reference state. Finally the results of the two procedures are combined to give the quantity of interest [Eq. (10)]... [Pg.20]

The reference state of A-electron theory becomes a reference vacuum state 4>) in the field theory. A complete orthonormal set of spin-indexed orbital functions fip(x) is defined by eigenfunctions of a one-electron Hamiltonian Ti, with eigenvalues ep. The reference vacuum state corresponds to the ground state of a noninteracting A-electron system determined by this Hamiltonian. N occupied orbital functions (el < pi) are characterized by fermion creation operators a such that a] ) =0. Here pt is the chemical potential or Fermi level. A complementary orthogonal set of unoccupied orbital functions are characterized by destruction operators aa such that aa < >) = 0 for ea > p and a > N. A fermion quantum field is defined in this orbital basis by... [Pg.79]

In the concentrated and marginal regimes of fig 5,3 a mean-field description, which neglects any spatial fluctuations, is appropriate. In these regimes, the solution is homogeneous and there is no chain-length dependence. Neither does the persistence p of the chains play a role since the Floiy-Huggins expressions do not contain the chain flexibility. This is so because the flexibility is assumed to be the same in the solution and in the reference state, so that p cancels in the entropy difference between the two states. [Pg.621]

The potential of a unit mass of groundwater, as given by Equation 1.3 is thus determined by its place in the earth gravitational field and by the pressure and density of the groundwater. In groundwater practice, sea level and atmospheric pressure are taken as reference state, i.e. Zq = 0 and pQ = 1 atmosphere. If, in addition, the density of the groundwater is constant (p, is not a function of p, i.e. the water is incompressible), the hydraulic head becomes... [Pg.4]


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See also in sourсe #XX -- [ Pg.104 ]




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