Generalized x-ray scattering factors in diatomic molecules

Journal Article · Fri Oct 31 23:00:00 EST 1975 · J. Chem. Phys., v. 63, no. 9, pp. 3786-3793

DOI:https://doi.org/10.1063/1.431871· OSTI ID:4122768

Stewart, R F; Bentley, J; Goodman, B

Generalized x-ray scattering factors for atoms (pseudoatoms) in diatomic molecules are determined from a finite multipole expansion of the charge density about each nucleus. The Fourier--Bessel coefficients of the pseudoatom radial density functions are determined by a least squares fit to the molecular form factor. All molecular one-center averages of the form are correctly given by the pseudoatom superposition whenever j < or = J, where J is the highest order multipole included in the a pseudoatom, regardless of the highest multipole order K for the b pseudoatom. To illustrate this property, a number of relationships between moments of the molecular charge distribution and of the pseudoatom are given. In addition, a sum rule relating the molecular form factor to the expectation values and is derived. For H$sub 2$ the theoretical, coherent x-ray scattering intensity is reproduced to about 1% for J=K=1 and to about 0.1% for J=K=2. (auth)

• Research Organization: Department of Chemistry, Carnegie-Mellon University, Pittsburgh, Pennsylvania 15213
• Sponsoring Organization: USDOE
• NSA Number: NSA-33-010262
• OSTI ID: 4122768
• Journal Information: J. Chem. Phys., v. 63, no. 9, pp. 3786-3793, Journal Name: J. Chem. Phys., v. 63, no. 9, pp. 3786-3793; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

*HYDROGEN-- X-RAY DIFFRACTION
640302* --Physics Research--Atomic
Molecular &amp; Chemical Physics--Atomic &amp; Molecular Properties
BESSEL FUNCTIONS
CHARGE DISTRIBUTION
EXPECTATION VALUE
FORM FACTORS
FOURIER ANALYSIS
HARTREE-FOCK METHOD
LEAST SQUARE FIT
MOLECULES
N60200* --Physics (Atomic &amp; Molecular)--Atomic &amp; Molecular Properties
SERIES EXPANSION
SUM RULES