请用Kröger-Vink符号写出方铁矿Fe1-xO中的主要点缺陷，并据此解释为什么氧分压越高，其中Fe²⁺的扩散反而越快。
Write down the dominant point defects of wuestite Fe1-xO in Kroger-Vink notation and explain, on that basis, why Fe2+ diffusion becomes faster as the oxygen partial pressure rises.
主要缺陷是带两个有效负电荷的铁空位V_Fe''与占据二价铁位的三价铁Fe_Fe•，两者按1:2的比例满足电中性。氧分压升高把更多Fe²⁺氧化为Fe³⁺，为维持晶格中性必须额外生成铁空位；而Fe²⁺正依赖空位机制跳跃迁移，空位浓度增大使扩散系数随之上升，这也造就了Fe1-xO极宽的非化学计量区。
The main defects are doubly negatively charged iron vacancies V_Fe'' and trivalent iron sitting on ferrous sites, Fe_Fe•, present in a 1:2 ratio that preserves electroneutrality. Higher oxygen pressure oxidizes more Fe2+ to Fe3+, which forces extra iron vacancies to keep the lattice neutral; since Fe2+ migrates by a vacancy-jump mechanism, the rising vacancy concentration increases its diffusivity, and the same coupling sustains the very broad nonstoichiometric range of Fe1-xO.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-04
来源 · Source
W. L. Roth,《Defects in the crystal and magnetic structures of ferrous oxide》,Acta Crystallographica,1960 (DOI: 10.1107/s0365110x60000297)
W. L. Roth, 'Defects in the crystal and magnetic structures of ferrous oxide', Acta Crystallographica, 1960, DOI: 10.1107/s0365110x60000297
独立核验依据 · Independent verification: 核验依据 1 Crossref DOI 10.1107/s0365110x60000297
#克罗格-文克符号 #铁空位 #非化学计量
太阳能板里的p-n结是干什么的？
What does the p–n junction in a solar panel do?
把p型和n型硅接在一起形成内建电场，光生电子-空穴对被分开，形成可对外供电的电流。
Joining p- and n-type silicon creates a built-in field that separates light-generated electron–hole pairs into a usable current.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
傅献彩 等,《物理化学》第5版,高等教育出版社,2005
Fu Xiancai et al., Physical Chemistry, 5th ed., Higher Education Press, 2005
独立核验依据 · Independent verification: 核验依据 2 DOUBAN ISBN 标识 9787040167696（按标识回读: 物理化学(第五版)上册）
#p-n结 #光伏 #内建电场
纯净的NaCl晶体无色透明，为什么经X射线辐照或在钠蒸气中加热后会变成黄褐色？
Why does colorless transparent NaCl turn yellow-brown after X-ray irradiation or heating in sodium vapor?
两种处理都会在晶格中留下氯离子空位：辐照直接制造空位并把电子留在其中，钠蒸气则带入过量金属，电离出的电子占据氯空位。被阴离子空位俘获的电子称为F心（色心），在可见光区有特征吸收带，NaCl的F带位于约465 nm处，吸收蓝紫色光后晶体即呈黄褐色；色心越密颜色越深，这类光谱也是研究点缺陷的经典手段。
Both treatments leave chloride vacancies in the lattice: irradiation creates them and traps electrons inside, while sodium vapor introduces excess metal whose ionized electrons fill chlorine vacancies. An electron captured by an anion vacancy is called an F-center (color center) and absorbs light in a characteristic visible band; the NaCl F-band sits near 465 nm, so the crystal takes on a yellow-brown hue. Denser color centers mean deeper color, and such spectra remain a classic probe of point defects.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
J. H. Schulman、W. D. Compton《Color Centers in Solids》，Pergamon Press，1962年
J. H. Schulman & W. D. Compton, "Color Centers in Solids", Pergamon Press, 1962
独立核验依据 · Independent verification: 核验依据 1 OPENLIBRARY 标识 /works/OL190347W：Color centers in solids（
#固态缺陷 #色心 #F心 #碱金属卤化物