Table 1. Rietveld analysis parameters obtained for LaB₆ and the mixture of polycrystalline NaCl and sodalite.

The Rietveld refinement was done using the FPA. The fitted parameters were the background (simulated with a Chebyshev polynomial with seven fittable parameters) and a preferred orientation according to March. Fixed parameters determined on an LaB₆ reference compound were ‘tube tails’ (a simple axial model for describing the axial divergence of the beam) and Lorentz polarization.

	Calibrant	Quantified mixture
Parameter	LaB6	NaCl	Sodalite
Data collection
Wavelength (Å)	1.540562	1.540562	1.540562
Monochromator	Ge(111)	Ge(111)	Ge(111)
No of scans averaged†	Up to 24	7	7
Exposure time per scan (mins)	12	15	15
Digitized step size (°)	0.012	0.012	0.012
2θ range used in RR‡ (°)	10–90	10–90	10–90
Unit-cell and refined parameters
Space group
a (Å)	4.15685 (9)	5.63982 (2)	8.87640 (4)
Cell volume (Å3)	71.828	179.389 (3)	699.375 (12)
Density (g cm−3)	4.7108 (4)	2.1640	2.3012
Lattice strain ɛ (°)	0.000032 (2)	0.00435 (1)	0.00109 (1)
Residual factors
R p, (%)	5.2, 16.9	4.2, 24.6
Sample composition
Purity of material (%)	99.9	>99	>99
Relative quantity weighed (%)		58.5 ± 0.3	41.5 ± 0.3
Relative quantity obtained from RR‡ (%)		60.0 ± 0.1	39.9 ± 0.1

^†For LaB₆, the sample was rotated by a few degrees after each exposure, while the mixture of NaCl and sodalite on the same sample holder was repeatedly irradiated keeping the same orientation of the sample holder.

^‡RR = Rietveld refinement.