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Integrals are invariant

Let us calculate the overlap integral S between two London orbitals centred at points C and D. After shifting the origin of the coordinate qfstem in eq. (G.13) by [Pg.674]

This means that when we use the London orbitals the results do not depend on the choice of vector potential origin. [Pg.674]

In the LCAO MO approximation, the dipole moment of the molecule can be divided into the sum of the atomic dipole moments and the dipole moments of the atomic pairs. [Pg.675]

In laser fields we may obtain a series of non-linear effects (proportional to higher powers of field intensity), including the doubling and tripling of the incident light frequency. [Pg.675]

A and f potentials contain, in principle (see Appendix G), the same information as the magnetic and electric field H and . There is an arbitrariness in the choice of A and f . In order to calculate the energy states of a system of nuclei (detectable in NMR spectroscopy) we have to use the Hamiltonian H given above, supplemented by the interaction of all magnetic moments related to the orbital and spin of the electrons and the nuclei. [Pg.676]


Like the overlap integrals, the multipole-moment integrals are invariant to an overall translation of the coordinate system. The sum of the derivatives of the integral (9.3.13) with respect to A, and C. must therefore be zero ... [Pg.346]

CO, CO, co, and o, respectively. The integrals in Eqs. (E.9) and (E.IO) will then be different from zero only if the integrands are invariant under all symmetry operations allowed by the symmetry point group, in particular under C3. It is readily seen that the linear terms in Q+ and Q- vanish in and H In turn. [Pg.626]

The role of symmetry in determining whether such integrals are non-zero can be demonstrated by noting that the integrand, considered as a whole, must contain a component that is invariant under all of the group operations (i.e., belongs to the totally... [Pg.596]

Assuming that U, and are invariant with respect to temperature and space, one can integrate equation 14 subject to equation 19, and obtain, after rearrangement, a basic heat-transfer equation for a parallel-flow heat exchanger (4). [Pg.485]

Thus, the orbitals uk and vk satisfy Hartree-Fock equations which are identical in form and differ only in the numerical values of the constants X/Jt and Ajk respectively. But since the latter are unknowns in the equation, and since 7(p) is itself invariant as shown in Eq. (21), we can say that the Hartree-Fock self-consistent-field equations are invariant under the orbital transformation given by Eqs. (5) and (6). This means in effect, that the energy integral ( H "X11/0 is minimized by the vk s as well as by the uk s — a circumstance which is in agreement with the invariance of and ( 1 under the transformation (5). [Pg.38]

They would become the stars of Prigoginian statistical mechanics. Their importance lies in the fact that, whenever it is possible to determine these variables by a canonical transformation of the initial phase space variables, one obtains a description with the following properties. The action variables / ( = 1,2,..., N, where N is the number of degrees of freedom of the system) are invariants of motion, whereas the angles a increase linearly in time, with frequencies generally action-dependent. The integration of the equations... [Pg.29]

The additional complexity of real chemical processes comes from the fact that they are invariably multistage processes with many reactors and separation units linked with complex configurations. One must then design each unit individually and then see how its design must be modified to be integrated into the entire process. [Pg.327]

In U(l) electrodynamics in free space, there are only transverse components of the vector potential, so the integral (158) vanishes. It follows that the area integral in Eq. (157) also vanishes, and so the U(l) phase factor cannot be used to describe interferometry. For example, it cannot be used to describe the Sagnac effect. The latter result is consistent with the fact that the Maxwell-Heaviside and d Alembert equations are invariant under T, which generates the clockwise... [Pg.115]

Exercise. Show that the integrals Lls L2, L3 are invariant for transformation of y, compare (IX.4.14). [Pg.313]

The classification scheme is particularly effective in arranging crystals by their charge transport properties. Integrated stack crystals (Sect. 2) and integral-oxidation state segregated stack crystals (Sect. 3) are invariably semiconductors, with typical room-temperature conductivities being a < 10 3 cm-1. In contrast, many of the non-... [Pg.5]

A catalytic system formed by Thr-1, Glu-17 and Lys-33 has been defined in the T. addophilum proteasome by structural and mutational studies. Close to Thr-1 are residues Ser-129, Ser-169 and Asp-166, which seem to be required for the structural integrity of the site but may also be involved in catalysis. These residues are invariant in the active subunits. The structure of the active sites of the bovine proteasome were compared by superimposing the functional amino acid residues Thr-1, Glu-17, Arg-19, Lys-33, Ser-129, Asp-166, Ser-169 and Gly-170. Root mean square (R.m.s.) deviations for all atoms of these functional residues in the active bovine subunit pairs p -p2, y l-y 5, and p2 ps were 0.4 A, 0.3 A and 0.4 A, respectively, demonstrating that the functional core of each active subunit is well conserved. [Pg.88]

Some features of a Phase I study are invariant others have changed considerably over time. On a periodic basis, a set of new investigators enters the field, and almost everyone is inclined to reinvent the design features of Phase I studies. First-in-human studies are an extraordinary opportunity to integrate pharmacokinetic (PK), pharmacodynamic (PD), and toxicology information while launching the new molecule on a path for rational clinical development (1). Above all, this is a major domain for application of the principles of clinical pharmacology. [Pg.473]

In traditional electronics - LCR circuits, for example - the Ls and the Cs are invariably oxide materials. In the area of integrated semiconductor devices, gate dielectrics [18], dielectrics in dynamic random access memories [19], ferroelectrics in non-volatile memories [20], and decoupling capacitors [21] are all oxide materials. Oxides are also at the heart of many fuel cell [22] and secondary battery materials [23]. [Pg.96]

The framework of a zeolite can be thought of as being made of finite component units or infinite component unit-like chains and layers. The concept of infinite component units, such as secondary building units (SBUs), was introduced by Meier[9,10]and Smith.[11] 18 kinds of SBUs that have been found to occur in tetrahedral frameworks[3] are shown in Figure 2.2. These SBUs, which contain up to 16 tetrahedrally coordinated atoms (T-atoms) are derived by assuming that the entire framework is made up of one type of SBU only. It should be noted that SBUs are invariably nonchiral. A unit cell always contains an integral number of SBUs.[12]... [Pg.24]

Similar to the ODF for texture, SODF can be subjected to a Fourier analysis by using generalized spherical harmonics. However, there are three important differences. The first is that in place of one distribution (ODF), six SODFs are analyzed simultaneously. The components of the strain, or the stress tensor can be used for analysis in the sample or in the crystal reference system. The second difference concerns the invariance to the crystal and the sample symmetry operations. The ODF is invariant to both crystal and sample symmetry operations. By contrast, the six SODFs in the sample reference system are invariant to the crystal symmetry operations but they transform similarly to Equation (65) if the sample reference system is replaced by an equivalent one. Inversely, the SODFs in the crystal reference system transform like Equation (65) if an equivalent one replaces this system and remain invariant to any rotation of the sample reference system. Consequently, for the spherical harmonics coefficients of the SODF one expects selection rules different from those of the ODF. As the third difference, the average over the crystallites in reflection (83) is structurally different from Equations (5)+ (11). In Equation (83) the products of the SODFs with the ODF are integrated, which, in comparison with Equation (5), entails a supplementary difficulty. [Pg.365]


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Invariant integral

Invariant integration

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