Standard X-ray Diffraction Powder Patterns

Potassium Zinc Decavanadete 16 Hydrate, K2Zn2V,,O2s '16H2O (triclinic)—ContinuedLattice constantsabca0y19551963Evans, Mrose and Marvin[1].National Bureau of Standards at 25 °C.A10, 7610. 778±.003A11. 1711. 146±.003A8. 778.774±. 003104° 50'104°57'±1'109° 29'109°32'±1'65°05'65°0'±2'Rubidium Chromate, Rb2CrO4Powder data cards. None.Additional published patterns. None.NBS sample. The sample of rubidium chromatewas obtained from the Fairmount ChemicalCo., Inc., Newark, N.J. Spectrographic analysisshowed the following major impurities: 0.1 to 1.0percent potassium; 0.01 to 0.1 percent sodium;and 0.001 to 0.01 percent each of aluminum,barium, calcium, and silicon.The color of the sample was yellow and it isoptically positive. The refractive indices areNa= 1.715, N0= 1.725, and N7= 1.759.The d-values of the three strongest lines are:3.207, 3.191, and 3.083 A.Structural data. Smith and Colby [1] in 1940determined that rubidium chromate has the potassium sulfate structure and the space groupD^-Pnam (No. 62) with 4(Rb2CrO4) per unit cell.The lattice constants reported by Smith andColby have been converted from kX to angstromunits for comparison with NBS values.19401963Smith andColbv [1].National Bureauof Standardsat 25° C.Lattice constantsaA7.9998. 001±.001boA10. 72610. 722±.001cA6. 3016.074±.001The density of rubidium chromate calculatedfrom NBS lattice constants is 3.657 g/cm3 at25° C.Reference[I] H. W. Smith, Jr. and M. Y. Colby, The crystal structure of rubidium chromate, B^CrO^ Z. Krist.103, 90-95 (1940).(orthorhombic)hkl020120200210121201130220211031002131221040230022310140122231320311212141240222330241150051042232400312401340420411123341, 251060213033430Internal Standard, 0Tungsten a = 3. 1648 ACu, 1.5405 A at 25 Cd' A5. 3654.4514. 0043. 7493. 5933. 3423. 2633.2073. 1913.0833. 0372.8722. 8382. 6802. 6642. 6442.5882.5412. 5092. 4422, 3882. 3802. 3592. 3442. 2262.2052. 1382. 0912.0712. 0212. 00982. 00352. 00101. 96971. 89971. 89081. 87371. 87031. 84261. 80471. 78591. 78131. 76211. 74617126143616181001009557413121833061154142214253011712411201812105796613151046