Technique for sample gap correction during experiments with diffractometer equipped with a curved position-sensitive detector

The effect of a sample gap in a diffractometer fitted out with a curve detector is analyzed. A method of correction of the effect of this gap on line positions is proposed. This technique has been used for data analyses of in situ diffraction experiments on mineral powder. The effects on line positions of the sample gap due to the thermal expansion of the sample holder have been corrected allowing cell parameters measurements despite the absence of reliable means of sample adjustement.