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Unitary structure factors

Since all the scatterers are identical, their structure factors can be normalised to unitary structure factors, as is always the case for homogeneous structures of normal scatterers [41] ... [Pg.17]

To deal with all the observations h e H in compact form, the unitary structure factor components can be arranged in a vector Urand, and the components of the constraint functions collected in a vector C(x). The MaxEnt distribution of electrons (x) then takes the form... [Pg.17]

Let us start with a set of unitary structure factors which are... [Pg.340]

We start with the process of normalisation in which the raw intensities are converted to unitary structure factors via the equation ... [Pg.346]

Unitary structure factor The ratio of the structure amplitude F b.kl) to its maximum possible value for point atoms at rest. [Pg.336]

The first mathematical relationships were obtained, starting about 1950, between the sign of phases in centrosymmetric structures in the form of inequalities, later extended to noncentrosymmetric structures, using unitary structure factors. [Pg.5163]

U i in the equation above is the unitary structure factor, defined thus ... [Pg.112]

In this section we have studied the shadow downstairs (in projective space) of the complex scalar product upstairs (in the linear space). We have found that although the scalar product itself does not descend, we can use it to define angles and orthogonality. Up to a phase factor, we can expand kets in orthogonal bases. We will use this projective unitary structure to define projective unitary representations and physical symmetries. [Pg.318]

Certain special features to be imposed on a model may be expressed by more complicated constraint equations. We note as an example the assumption of a rigid molecule with prescribed dimensions whose position and orientation are to be refined. The position may be described by the coordinates of the centre of mass and the orientation by three Euler angles with respect to a unitary coordinate system. The atomic coordinates and thus the structure factor. Equation [1], are expressed as functions of these six parameters. The latter may then be adjusted to optimize the deviance. A similar procedure can be used to constrain the atomic displacement parameters of a molecule to rigid-body movements described by a translation tensor, a libration tensor and a transla-tion/libration-correlation tensor (TLS model). This model neglects intramolecular vibrations. [Pg.1110]

It is worth mentioning that Eq. 9 derives from Eq. 4, with the following assumptions (1) a unitary participation factor is considered for the ground acceleration, while the principal mode participation factor is considered according to Eq. 10a. (2) The spectral acceleration RsCTJ is considered for the evaluation of the floor relative acceleration instead of the spectral relative normalized acceleration (Rs(Ts) — 1). (3) The ground acceleration and the relative structural acceleration are combined through the SRSS (Square Root of the Sum of the Squares) combination mle (Table 4 and Eig. 9). [Pg.2495]

Ian Deary (2000, this volume) and Arthur Jensen (2000, this volume) have rightly argued that we must distinguish between the species-typical human cognitive architecture (which may be massively modular), and the factor-analytic structure of individual differences in cognitive functioning (which yields a unitary factor). This distinction is obvious in the case of fitness itself to claim that there is an f factor in a particular species (which can capture individual differences in... [Pg.265]

In Section 2 we discuss the Lie algebra structure of Fermi-Fock space, which is the direct sum of all of the state spaces W, in Section 3 we will describe the possible decompositions of the Lie algebra u 2s) of U 2s), the one-particle group associated with, and thus the factorizations of U (25) that lead to manifolds of CSs in that can be based on U 2s). In Section 4 we study in detail the forms of AGP CSs. We also show how the CS construction applied to the unitary group of A-electron space can reproduce the familiar configurational interaction expansion. We conclude with a summary and discussion in Section 5. [Pg.111]


See other pages where Unitary structure factors is mentioned: [Pg.291]    [Pg.291]    [Pg.291]    [Pg.291]    [Pg.77]    [Pg.233]    [Pg.79]    [Pg.24]    [Pg.12]    [Pg.258]    [Pg.201]    [Pg.68]    [Pg.212]    [Pg.419]    [Pg.383]    [Pg.696]    [Pg.197]    [Pg.218]   
See also in sourсe #XX -- [ Pg.336 ]




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