[Cu₂ZnTeO₄]²⁺[SO₄·H₂O]²⁻ crystallizes as a category IV order‒disorder (OD) structure with two kinds of nonpolar layers with the formal composition [Cu₂ZnTeO₄]²⁺ and [SO₄·H₂O]²⁻, respectively. Reflection symmetry that is only valid for the [Cu₂ZnTeO₄]²⁺ layers leads to two ways of placing the [SO₄·H₂O]²⁻ layers. Two of the polytypes are of a maximum degree of order (MDO₁: P2₁/m and MDO₂: Pnma). The crystal under investigation is mostly of the MDO₂ polytype. Remaining positive electron density peaks in the difference Fourier maps indicate fragments of the MDO₁ polytype.

中文翻译：

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[Cu2ZnTeO4] 2+ [SO4·H2O] 2-的有序（OD）多态性

[Cu ₂ ZnTeO ₄ ] ²⁺ [SO ₄ ·H ₂ O] ²⁻结晶为IV类有序无序（OD）结构，具有两种非极性层，其正式组成为[Cu ₂ ZnTeO ₄ ] ²⁺和[ SO ₄ ·H ₂ O] ²⁻。仅对[Cu ₂ ZnTeO ₄ ] ²⁺层有效的反射对称性导致了两种放置[SO ₄ ·H ₂ O] ^2-层的方式。两个多型体的最大有序度（MDO₁：P 2 ₁ / m和MDO ₂：Pnma）。研究中的晶体大多数是MDO ₂多型的。差异傅立叶图中的剩余正电子密度峰指示MDO ₁多型的片段。