Melilite
Armbruster T, Rothlisberger F
American Mineralogist 75 (1990) 963-969
Crystal growth and structures of mixed-anion silicates-germanates:
Ca5[(Ge,Si)2O7][(Ge,Si)O4] and Na2Ca6[Si2O7][SiO4]2
sample Ca5Ge2.23Si.77O11
_database_code_amcsd 0001318
10.912 8.695 11.000 90 96.87 90 C2/m
atom      x     y     z occ U(1,1) U(2,2) U(3,3) U(1,2) U(1,3) U(2,3)
Ge1   .5606     0 .2709 .73 0.0045 0.0125 0.0081      0 0.0001      0
Si1   .5606     0 .2709 .27 0.0045 0.0125 0.0081      0 0.0001      0
Ge2   .8106     0 .4631 .81 0.0094 0.0059 0.0068      0 -.0009      0
Si2   .8106     0 .4631 .19 0.0094 0.0059 0.0068      0 -.0009      0
Ge3   .7947     0 .0177 .69 0.0044 0.0079 0.0083      0 -.0002      0
Si3   .7947     0 .0177 .31 0.0044 0.0079 0.0083      0 -.0002      0
Ca1  -.0162     0 .2497     0.0060 0.0292 0.0077      0 -.0008      0
Ca2   .2701 .1876 .2436     0.0092 0.0073 0.0167 -.0020 -.0043 0.0010
Ca3       0 .2890     0     0.0161 0.0298 0.0113      0 0.0050      0
Ca4      .5 .1768    .5     0.0212 0.0208 0.0233      0 -.0023      0
O1    .4187     0 .3234      0.005  0.016 0.014       0  0.001      0
O2    .8536 .1540 .1035      0.010  0.012 0.012  -0.002 -0.001 -0.002
O3    .8701 .1546 .3925      0.011  0.008 0.014  -0.002      0  0.003
O4    .8570     0 .8795      0.017  0.016 0.014       0  0.007      0
O5    .6490     0 .4208      0.010  0.018 0.009       0  0.000      0
O6    .1648     0 .3813      0.004  0.023 0.012       0 -0.002      0
O7    .8594    .5 .0267      0.013  0.012 0.050       0  0.007      0
O8    .5889 .8281 .2070      0.016  0.032 0.020   0.011 -0.008 -0.012