Nb2 O7 Tl2
      Fourquet J, Duroy H, Lacorre P
      Journal of Solid State Chemistry 114 (1995) 575-584
      Tl2 Nb2 O6+x (0<x<1): a continuous cubic pyrochlore type solid solution
      _cod_database_code 1000387
      _database_code_amcsd 0013839

      CELL PARAMETERS:   10.6220  10.6220  10.6220   90.000   90.000   90.000
      SPACE GROUP: Fd3m      
      X-RAY WAVELENGTH:     1.541838
      Cell Volume:   1198.447
      Density (g/cm3):      5.566
      MAX. ABS. INTENSITY / VOLUME**2:      191.4389351    
      RIR:     11.200
      RIR based on corundum from Acta Crystallographica A38 (1982) 733-739
               2-THETA      INTENSITY    D-SPACING   H   K   L   Multiplicity
                14.44          2.27        6.1326    1   1   1         8
                29.12        100.00        3.0663    2   2   2         8
                33.75         34.21        2.6555    4   0   0         6
                36.89          2.82        2.4369    3   3   1        24
                48.48         36.48        1.8777    4   4   0        12
                57.56         38.24        1.6013    6   2   2        24
                60.38         12.25        1.5332    4   4   4         8
                70.99          5.89        1.3277    8   0   0         6
                78.50         13.62        1.2184    6   6   2        24
                80.96         11.75        1.1876    8   4   0        24
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       XPOW Copyright 1993 Bob Downs, Ranjini Swaminathan and Kurt Bartelmehs
  For reference, see Downs et al. (1993) American Mineralogist 78, 1104-1107.