Standard X-ray Diffraction Powder Patterns

Cadmium Perchlorate Hexahydrate, Cd(ClO4) 2 -6H2O (trigonal)Powder data cards. None.Additional published patterns. None.NBS sample. The sample of cadmium perchloratehexahydrate was obtained from the CityChemical Corp., New York, N.Y. Spectrographicanalysis showed the following major impurities:0.0001 to 0.001 percent each of lead and silicon.The sample was colorless and optically negativewith indices of refraction N 0—1.490 and N e=1.479.The d-values of the three strongest lines are:3.995, 4.223, and 2.902A.Structural data. West [1] in 1935 reported thatcadmium perchlorate hexahydrate is trigonal, thespace group CJv-P3ml (No. 156) with l[Cd(ClO4 )2-6H2O] per unit cell. West reported that thestructure is very similar to the hexagonal magnesium perchlorate structure. Moss, Russell, andSharp [2] confirmed West's determinations. Thevalue of "a" reported by West has been dividedby 2 as he suggested. The unit cell values reportedby West have been converted from kX to angstromunits for comparison with the NBS values.19351963Lattice constantsWest [!]...__. ._._....National Bureau ofStandards at 25 °C__aA7. 927. 9939cA5. 305. 3304The density of cadmium perchlorate hexahydrate calculated from the NBS lattice constantsis 2.361 g/cm3 at 25 °C.References[1] C. D. West, The crystal structures of hydrated compounds. II. Structure type Mg(ClO4)2-6H 20, Z.Krist. A91, 480-493 (1935).[2] K. C. Moss, D. R. Russell, and D. W. A. Sharp, Thelattice constants of some metal fluoroborate hexahydrates,Acta Cryst. 14, 330 (1961).hkl100001101110200111201002210102211300112301202220310212311003302103401113320203312321410213411402303322501004, 330420313421114204403502511214323422600413512224Intern a I Standard,Tungsten, a==3.1648 ACu, 1.5405 1 at 25 CdA6.9215.3264. 2233. 9953. 4633. 1972. 9022. 6672. 6172. 4892.3502. 3092.2172. 1172. 1119.9985. 9201. 8670. 8064. 77711. 74461. 72051. 64631. 62311. 58801. 58081. 55771. 52231. 51071. 47001. 45391. 45191. 40781. 36421. 34021. 33251. 30821. 30421. 27051. 26411. 24381. 24001. 22871. 21071. 18721. 18411. 17431. 15371. 15101. 12701. 1088/25177510045166211825972627198379367434956651111234425443325233333319