New Approaches to the Diffractometer Calibration. Study of InSb in the 90-490 K Temperature Range

New techniques for the calibration of single-crystal diffractometers equipped with a 2D detector are proposed to improve the accuracy of measuring the unit cell parameters. According to these methods, reflection profiles are processed using the original SearchXY-2θ program, and the detector position is refined by recording an external reference. Details of the calibration of diffractometers equipped with a three- or four-circle goniometer are discussed. The use of reflections with 2θ ≈ 100° when refining the unit cell parameters of a test InSb single crystal allowed measuring parameter a of the cubic unit cell with a relative error of 7·10 –5 . The possibilities of the techniques are also demonstrated on the measurements of the a ( T ) dependence for InSb in the range of 90-490 K.