120 likes | 342 Views
Chapter 27 – SINGLE PARTICLE FORM FACTORS. 27:2. FORM FACTOR FOR A UNIFORM SPHERE. 27:3. SPHERICAL CORE-SHELL. 27:5. FORM FACTORS FOR CYLINDRICAL SHAPES. 27:8. PAIR CORRELATION FUNCTIONS. 27:2. FORM FACTOR FOR A UNIFORM SPHERE. Definition of the form factor:. Uniform density sphere:.
E N D
Chapter 27 – SINGLE PARTICLE FORM FACTORS 27:2. FORM FACTOR FOR A UNIFORM SPHERE 27:3. SPHERICAL CORE-SHELL 27:5. FORM FACTORS FOR CYLINDRICAL SHAPES 27:8. PAIR CORRELATION FUNCTIONS
27:2. FORM FACTOR FOR A UNIFORM SPHERE Definition of the form factor: Uniform density sphere: Spherical Bessel function: Final result:
case 2 case 1 case 3 R T R T 27:3. SPHERICAL CORE-SHELL
z Q q y f x 27:5. FORM FACTORS FOR CYLINDRICAL SHAPES Form factor: Uniform density cylinder: Longitudinal: Perpendicular: Cylindrical Bessel functions: Therefore: But: Result for perpendicular form factor: Final result:
SPECIAL CASES Disk of radius R and negligible thickness: Infinitely thin rod of length L: Sine integral function:
R r r’ FORM FACTOR FOR A SPHERE Density-density correlation function: Fourier transform: Radial pair correlation function:
COMMENTS -- Single-particle form factors dominate scattering for dilute systems. -- Form factors are an essential component for molecular models used for data analysis.