The crystal structure of arsenic at 4.2, 78 and 299DegreesK
AbstractThe lattice constants and the atomic position parameter, z, of a high purity, low strain, single-crystal of arsenic have been determined. Low extinction reflections of filtered Mo K and Ag K radiation were used for the determination of z. The Bond precision technique with Mo K radiation was used for the determination of the unit-cell dimensions a and c. Average values for a and c in A, and for z are: 4.2DegreesK z = 0.22764 a = 3.7597 c = 10.4412; 78DegreesK z = 0.22754 a = 3.7595 c = 10.4573; 299plus or minus3DegreesK z = 0.22707 a = 3.7598 c = 10.5475. The estimated standard deviation of z is plus or minus0.00004 at 4.2DegreesK, plus or minus0.00002 at 78DegreesK and plus or minus0.00005 at 299DegreesK. The precision of a is estimated to be plus or minus0-0001 A and that for c to be plus or minus0.0002 A. The results for As are compared with those reported earlier for Sb and Bi.