Suzukiite from the Mogurazawa mine, Gunma Prefecture, Japan exhibits orthorhombic space group
Cmcm,
a = 5.3546(16),
b = 15.249(5),
c = 7.094(2) Å,
Z = 2. Electron microprobe analyses yielded the empirical formula (Ba
0.977Sr
0.027)
Σ1.004V
1.013Si
1.985O
7. The crystal structure was refined to
R = 0.0211. The crystal structure of suzukiite comprises BaO
11 polyhedra, SiO
4 tetrahedra, and VO
5 square pyramids. The Si
4O
12 chain runs parallel to the
c axis, and the VO
5 square pyramids link the chains to form a layer parallel to the
ac plane. Ba atoms are located in the interlayer region and stack alternatively with the silicate–vanadate layers. The coordination of Ba in suzukiite is considerably distorted owing to the tight framework of the silicate–vanadate layer. The
b length of the unit cell of suzukiite is larger than that of haradaite, the Sr analogue, whereas the
a and
c lengths show no remarkable difference.
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