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[marquardt_constant !E]…
Allows for changing the Marquardt constants, the Simulated_Annealing_1 macro changes the Marquardt constants as follows:
load marquardt_constant { 0 1 }
[min_r #] [max_r #]
Defines the minimum and maximum radii for calculating bond lengths. min_r and max_r are by default set to 0 and 3.2 Å respectively.
[mixture_density_g_on_cm3 !E]
Calculates the density of the mixture assuming a packing density of 1, see also mixture_MAC.
[mixture_MAC !E]
Calculates the mass absorption coefficient in cm2/g for a mixture as follows:
where wi and (m/r)i is the weight percent and phase_MAC of phase i respectively. Errors are reported for phase_MAC and mixture_MAC.
The following example provides phase and mixture mass absorption coefficients.
xdd…
mixture_MAC 0
str…
phase_MAC 0
The macros Mixture_LAC_1_on_cm, Phase_LAC_1_on_cm and Phase_Density_g_on_cm3 calculates the mixture and phase linear absorption coefficients (for a packing density of 1) and phase density, for example:
xdd…
Mixture_LAC_1_on_cm(0)
str…
Phase_Density_g_on_cm3(0)
Phase_LAC_1_on_cm(0)
Errors for these quantities are also calculated. Mass absorption coefficients obtained from NIST at http://physics.nist.gov/PhysRefData/XrayMassCoef are used to calculate mixture_MAC and phase_MAC.