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Rotation matrix definition

If we recall the definition of the rotation matrix 0, x) from equation (5.45) and... [Pg.158]

Some types of matrices that appear frequently are Hermitian matrices, for which A = A anti-Hermitian matrices, for which A = — A and unitary matrices, for which = U The MCSCF methods diseussed in most detail in this review will involve only operations of real matrices. In this case these matrix types reduce to symmetric matrices, for which A = A , antisymmetric matrices, for which A = — A, and orthogonal matrices, for which U = U. A particular type of orthogonal matrix is called a rotation matrix and satisfies the relation Det(R)= -I-1, where Det(R) is the usual definition of a determi-... [Pg.68]

If the group is rotational or helical and ij> is not 5-type, then the />, on each site become linear combinations of basis functions related by the rotation matrix of the appropriate angular momentum and the appropriate rotational or helical step angle [27]. It is traditional to use Cartesian-Gaussian orbital basis sets in quantum-chemical calculations [28], but solid-spherical-harmonic Gaussians [29] are best for symmetry adaption and matrix element evaluation. Including an extra factor of (-)M in the definition of the solid spherical harmonics [30]... [Pg.155]

If we recall the definition ofthe rotation matrix 9) , ((/>, 9, x) from equation (5.45) and integrate over the volume element dry = sin0 d< d0 dx, we obtain... [Pg.158]

The Kronecker product with the identity ensures rotational invariance (sphericalness) elliptical Gaussians could be obtained by using a full n x n A matrix. In the former formulation of the basis function, it is difficult to ensure the square integrability of the functions, but this becomes easy in the latter formulation. In this format, all that is required is that the matrix, A, be positive definite. This may be achieved by constructing the matrix from a Cholesky decomposition A), = Later in this work we will use the notation... [Pg.435]

Due to the particular effects of the microwaves on matter (namely dipole rotation and ionic conductance), heating of the section, including its core, occurs instantaneously, resulting in rapid breakdown of protein crosslinkages. Furthermore, the extraction and recovery of a solute from a solid matrix with microwave heating is routinely obtained in the field of analytical chemistry (Camel, 2001). However, a definite, full explanation of the effects of microwave heating on the molecular aspect of antigen retrieval is awaited. [Pg.131]

You will find that many of the sources do not use exactly the same matrix representations for some of the product operators and rotation matrices. The exact form of the density matrix depends on the numbering of the spin states and on certain conventions that are not consistent in the literature. In the above examples, the definitions are consistent with the product operator methods and with themselves. [Pg.488]

In order to assign the Zeeman patterns for the three lowest rotational levels quantitatively, one must determine the spacings between the rotational levels, and the values of g/and gr-In the simplest model which neglects centrifugal distortion, the rotation spacings are simply B0. /(./ + 1) this approximation was used by Brown and Uehara [10], who used the rotational constant B0 = 21295 MHz obtained by Saito [12] from pure microwave rotational spectroscopy (see later in the next chapter). The values of the g-factors were found to be g L = 0.999 82, gr = —(1.35) x 10-4. Note that because of the off-diagonal matrix elements (9.6), the Zeeman matrices (one for each value of Mj) are actually infinite in size and must be truncated at some point to achieve the desired level of accuracy. In subsequent work Miller [14] observed the spectrum of A33 SO in natural abundance 33 S has a nuclear spin of 3/2 and from the hyperfine structure Miller was able to determine the magnetic hyperfine constant a (see below for the definition of this constant). [Pg.590]

From what has been shown in the preceding sections (cf. Eqs. 61 and 73, 83), it is possible to present the molecular structure resulting from both the r -fit method and any of the r()-derived methods in a convenient and easily comparable form, as a structural description in both Cartesian and internal coordinates, and with consistent errors and correlations (for small and larger molecules). A detailed comparison would require a sufficiently large SDS to determine a complete molecular structure, but the requirements are still the least restrictive of all methods presented. The input data must include the covariance matrix of the rotational constants or moments. This matrix may have to be adequately modeled to avoid grossly different weighting of isotopomers which is usually not warranted. The definition of the input data set... [Pg.110]

Here r is a 3n x 1 vector of Cartesian coordinates for the n particles, Lk is an n x n lower triangular matrix of rank n and I3 is the 3x3 identity matrix, k would range from 1 to A where N is the number of basis functions. The Kronecker product with I3 is used to insure rotational invariance of the basis functions. Also, integrals involving the functions k are well defined only if the exponent matrix is positive definite symmetric this is assured by using the Cholesky factorization LkL k. The following simplifications will help keep the notation more compact ... [Pg.31]

The present stage is suitable for the introduction of the Coriolis coupling constants, f%k 63, 64). This may seem curious, but it is in accordance with the fact that these constants are appropriate only when rectilinear coordinates are involved. This will be further discussed below in relation to the vibration-rotation part of the G-matrix. Here it is convenient to give a general definition,... [Pg.121]

The definitions of the terms can be found in [30], but it is sufficient here to note that Ka represents the vibrational kinetic energy operator, Ep the electronic energy, Vn the nuclear repulsion operator, and the terms b and bo are elements of a matrix closely related to the inverse of the instantaneous inertia operator matrix. It should also be noted that the y terms arise from the interaction of the rotational with the electronic motion and tend to couple electronic states, even those diagonal in k. [Pg.117]


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See also in sourсe #XX -- [ Pg.275 ]




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