Gonnardite
Lee Y, Hriljac J A, Vogt T
American Mineralogist 90 (2005) 247-251
Variable-temperature structural studies of tetranatrolite from Mt. Saint-Hilaire:
Synchrotron X-ray powder diffraction and Rietveld analysis
Sample: at ambient conditions
13.1988 13.1988 6.6288 90 90 90 I-42d
atom     x     y     z  occ  Uiso
SiT1     0     0     0 .537 .0080
AlT1     0     0     0 .463 .0080
SiT2 .0550 .1326 .6210 .537 .0080
AlT2 .0550 .1326 .6210 .463 .0080
O1   .3918   .25  .125      .0120
O2   .1339 .0607 .4780      .0120
O3   .0526 .0951 .8662      .0120
Na   .6923   .25  .125 .731 .0268
Ca   .6923   .25  .125 .237 .0268
Wat4 .1277   .25  .125       .038
Wat5  .875   .25  .125 .370  .038