xraytools - Absorption Coefficient Calculator

chemical formula:

C₃₂H₂₆N₂O₂Ni₁

molar mass:

529.2534 g/mol

density:

1.237 g/cm³

mass absorption coefficient (Mo):

ν = 5.77 cm²/g

mass absorption coefficient (Cu):

ν = 9.52 cm²/g

linear absorption coefficient (Mo):

ν = 7.135 cm^-1

= 0.714 mm^-1

linear absorption coefficient (Cu):

ν = 11.78 cm^-1

= 1.178 mm^-1

Generally, Mo radiation provides a higher resolution and more reflections compared to Cu radiation and should thus be considered to be the standard case. Cu radiation yields better reflection intensities, which is useful especially for weakly scattering crystals.
When the absolute configuration of a chiral compound is to be resolved (see also: Friedif Calculator) or a very large unit cell is expected, Cu radiation may be preferable.
The linear absorption coefficient of matter towards Cu radiation is generally higher and should not exceed 10 mm^-1.
for an exemplary calculation, see here
mass absorption coefficients taken from here (1 ≤ Z ≤ 83; based on H. P. Klug and L. E. Alexander, X-Ray Diffraction Procedures: For Polycrystalline and Amorphous Materials, Wiley, 2nd edn., 1974.)
atomic masses taken from here (1 ≤ Z ≤ 118)
for the estimation of crystal densities, the very rough assumption of an atomistic volume of 18 Å³ per non-hydrogen atom is made

Timo Stein, 2019