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Symmetry space

To see why this is so, let us attempt to apply the procedure of Section II.B to a bound-state wave function. This is illustrated schematically in Fig. 19. It is clear immediately that we cannot construct an unsymmetric in the double space, because each bound-state eigenfunction must be an irreducible representation of the double-space symmetry group. Thus a bound-state function in the double space is necessarily symmetric or antisymmetric under R2k, and is thus either a Fq or a Fn function. For a Fq function, we have Fn = 0 (since and Fn cannot form a degenerate pair), which implies [from Eq. (6)] that... [Pg.36]

After the discovery of the combined charge and space symmetry violation, or CP violation, in the decay of neutral mesons [2], the search for the EDMs of elementary particles has become one of the fundamental problems in physics. A permanent EDM is induced by the super-weak interactions that violate both space inversion symmetry and time reversal invariance [11], Considerable experimental efforts have been invested in probing for atomic EDMs (da) induced by EDMs of the proton, neutron, and electron, and by the P,T-odd interactions between them. The best available limit for the electron EDM, de, was obtained from atomic T1 experiments [12], which established an upper limit of de < 1.6 x 10 27e-cm. The benchmark upper limit on a nuclear EDM is obtained from the atomic EDM experiment on Iyt,Hg [13] as d ig < 2.1 x 10 2 e-cm, from which the best restriction on the proton EDM, dp < 5.4 x 10 24e-cm, was also obtained by Dmitriev and Senkov [14]. The previous upper limit on the proton EDM was estimated from the molecular T1F experiments by Hinds and co-workers [15]. [Pg.241]

Superconducting phases with broken space symmetries... [Pg.213]

For small asymmetries, the superconducting state is homogeneous and the order parameter preserves the space symmetries. For most of the systems of interest the number conservation should be implemented by solving equations for the gap function and the densities of species self-consistently. In such a scheme the physical quantities are single valued functions of the asymmetry and temperature, contrary to the double valued results obtained in the non-conserving schemes. [Pg.222]

Within a variational treatment, the relative contributions of the spin-and space-symmetry adapted CSFs are determined by solving a secular problem for the eigenvalues (E)) and eigenvectors (CQ of the matrix representation H of the full many-electron Hamiltonian H within this CSF basis ... [Pg.208]

The spin- and space-symmetry of the < >[ determine the symmetry of the state T whose energy is to be optimized. [Pg.333]

Two forms of symmetry notation are commonly used. As chemists, you will come across both. The Schoenflies notation is useful for describing the point symmetry of individual molecules and is used by spectroscopists. The Hermann-Mauguin notation can be used to describe the point symmetry of individual molecules but in addition can also describe the relationship of different molecules to one another in space—their so-called space-symmetry—and so is the form most commonly met in crystallography and the solid state. We give here the Schoenflies notation in parentheses after the Hermann-Mauguin notation. [Pg.13]

As is well-known in particle physics, a dipole is a broken 3-space symmetry in the violent flux exchange between the active vacuum and the dipole. [Pg.651]

This dipole s broken 3-space symmetry in EM energy flow, provides a relaxation to a more fundamental EM energy flow symmetry in 4-space where P and T symmetries are broken but CPT symmetry is maintained. [Pg.651]

A broken 3-space symmetry exists of a magnetic dipole [18] of a permanent magnet, well known in particle physics since 1957 but inexplicably not yet added into classical electrodynamics theory, wherein the broken symmetry of the magnetic dipole rigorously requires that the dipole continually absorb magnetic energy from the active vacuum in unusable form, and that the... [Pg.733]

Broken 3-space symmetry initiates jump to 4-space symmetry between complex plane and real plane. Energy flow is now conserved in 4-space, but not in 3-space. This is the true negative resistor effect, and a negentropic reordering of the vacuum. [Pg.748]

Class 3 is obtained by introducing a twofold axis of rotation, symbolized by below the motif on the line of translation. The important thing to note here is that in addition to the C2 operation explicitly introduced (and all those just like it obtained by unit translation) a second set of C2 operations, with axes halfway between those in the first set is created. In space symmetry (even in ID space) the introduction of one set of (equivalent) symmetry elements commonly creates another set, which are not equivalent to those in the first set. It should also be noted that had we chosen to introduce explicitly the... [Pg.349]

We may create several new 2D space symmetries by adding rotational symmetry. As we have seen, only axes of orders 2, 3, 4, and 6 are possible. [Pg.358]

Another way to create new 2D space symmetries is to introduce reflection lines to the preceding ones. This can be done only for the rectangular, square, trigonal, and hexagonal lattices. If one set of planes is introduced, parallel to one of the translation directions, we get the symmetry pm. It is to be noted that a second set of reflection lines, interleaving the introduced set arises automatically. [Pg.361]

In the following sketches and patterns (a-i) you will find several of the seventeen 2D space symmetries represented. Examine each sketch, identify its symmetry group, and draw a diagram that shows all the symmetry elements. [Pg.410]

Complete Cl, or full Cl, is configuration interaction with a configuration list which includes all possible configurations of proper spin and space symmetry in the chosen orbital space. As has been mentioned previously, the number of configurations in complete Cl will depend in an n-factorial way on the number of electrons and the number of orbitals and it will therefore quickly become too large to be handled. This method is therefore not very well suited as a standard model to solve quantum chemical problems. There are, however, two situations where an efficient complete Cl method is useful to have. The first of these is in connection with the CASSCF method which has been described in another chapter. The other is in connection with bench mark tests. Since any other Cl method selects configurations after some principle, a comparison to complete Cl is the way to check these principles out. We will therefore in this section briefly outline the main steps in the complete Cl method as it is carried out today. [Pg.285]


See other pages where Symmetry space is mentioned: [Pg.273]    [Pg.488]    [Pg.104]    [Pg.105]    [Pg.144]    [Pg.36]    [Pg.44]    [Pg.46]    [Pg.62]    [Pg.252]    [Pg.214]    [Pg.270]    [Pg.58]    [Pg.205]    [Pg.208]    [Pg.357]    [Pg.358]    [Pg.364]    [Pg.382]    [Pg.383]    [Pg.389]    [Pg.662]    [Pg.358]    [Pg.361]    [Pg.362]    [Pg.264]    [Pg.358]   
See also in sourсe #XX -- [ Pg.10 ]




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Application of space group symmetry in crystal structure determination

Continuous Space-Time Symmetries

Crystal Symmetry and Space Groups

Crystal symmetries space groups

Determination of a Space Group Symmetries

Diffraction space symmetries

Discrete Space-Time Symmetries

General Space-Time Symmetries

Momentum space symmetry

Permutational symmetry two-dimensional Hilbert space model

Pseudo-symmetry, space-group

Site Symmetry and Induced Representations of Space Groups

Space Symmetry in Liquid Crystals

Space group symmetries Crystallographic symmetry

Space group symmetry

Space group symmetry and its mathematical representation

Space group symmetry symbols

Space groups, symmetry diagrams

Space lattices symmetry operations

Space symmetry three-dimensional

Space-, Spin- and Overall Symmetry

Space-group frequency 207 symmetry

Space-groups symmetries dimensionality

Space-groups symmetries glide-reflection

Space-groups symmetries identity period

Space-groups symmetries similarity symmetry

Space-groups symmetries spirals

Space-groups symmetries translation presence

Space-inversion symmetry

Symmetries space groups and

Symmetry in reciprocal space

Symmetry of three-dimensional patterns space groups

Symmetry operators space inversion

Symmetry space group examples

The Symmetry Space Groups

Three-dimensional periodic symmetry space groups

Translation and Space Symmetry of Crystalline Orbitals Bloch Functions

Use of Symmetry in Reciprocal Space

Visualization of space group symmetry in three dimensions

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