<p><b>二碘化鎢</b>是鎢的一種碘化物，化學式為[W<sub>6</sub>I<sub>8</sub>]I<sub>4</sub>，或簡寫為WI<sub>2</sub>。
</p>
<h2><span id=".E5.88.B6.E5.A4.87"></span><span id="制备">製備</span></h2>
<p>二碘化鎢可以由三碘化鎢分解而成。</p>
<dl><dd><span><span><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \mathrm {6\ WI_{3}\longrightarrow [W_{6}I_{8}]I_{4}+3\ I_{2}} }">
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    <annotation encoding="application/x-tex">{\displaystyle \mathrm {6\ WI_{3}\longrightarrow [W_{6}I_{8}]I_{4}+3\ I_{2}} }</annotation>
  </semantics></math></span></span></dd></dl><p>它也可以由二氯化鎢和碘化物的置換反應而成。</p>
<dl><dd><span><span><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \mathrm {[W_{6}Cl_{8}]Cl_{4}+12\ I^{-}\longrightarrow [W_{6}I_{8}]I_{4}+12Cl^{-}} }">
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  </semantics></math></span></span></dd></dl><p>它也可以由鎢和碘直接反應而成，此為可逆反應。這個反應可用於鹵素燈中。</p>
<dl><dd><span><span><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \mathrm {W+I_{2}\rightleftharpoons WI_{2}} }">
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    <annotation encoding="application/x-tex">{\displaystyle \mathrm {W+I_{2}\rightleftharpoons WI_{2}} }</annotation>
  </semantics></math></span></span></dd></dl><p>六羰基鎢和碘反應，也可以得到二碘化鎢。</p>
<h2><span id=".E6.80.A7.E8.B4.A8"></span><span id="性质">性質</span></h2>
<p>二碘化鎢是一種深土色固體，在空氣和濕氣中穩定。它的結構和二氯化鎢一樣，為正交晶系，空間群 Bbem (No. 64)，晶格參數 <i>a</i> = 1258 pm、<i>b</i> = 1259 pm、<i>c</i> = 1584 pm。</p>
<h2><span id=".E5.8F.82.E8.80.83.E8.B5.84.E6.96.99"></span><span id="参考资料">參考資料</span></h2>
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**二碘化鎢**是鎢的一種碘化物，化學式為 [W6I8]I4，或簡寫為 WI2。

## 製備

二碘化鎢可以由三碘化鎢分解而成。

　
: $\mathrm {6\ WI_{3}\longrightarrow [W_{6}I_{8}]I_{4}+3\ I_{2}} $

它也可以由二氯化鎢和碘化物的置換反應而成。

　
: $\mathrm {[W_{6}Cl_{8}]Cl_{4}+12\ I^{-}\longrightarrow [W_{6}I_{8}]I_{4}+12Cl^{-}} $

它也可以由鎢和碘直接反應而成，此為可逆反應。這個反應可用於鹵素燈中。

　
: $\mathrm {W+I_{2}\rightleftharpoons WI_{2}} $

六羰基鎢和碘反應，也可以得到二碘化鎢。

## 性質

二碘化鎢是一種深土色固體，在空氣和濕氣中穩定。它的結構和二氯化鎢一樣，為正交晶系，空間群 Bbem (No. 64)，晶格參數 _a_ = 1258 pm、_b_ = 1259 pm、_c_ = 1584 pm。

## 參考資料
13470-17-2