Data for: Rates and Products of Oxidation of Ferrous Iron in Trioctahedral Smectites

Data package for manuscript "Rates and Products of Oxidation of Ferrous Iron in Trioctahedral Smectites", by Robert J. Kupper, Nanqing Zhou, Clara S. Chan, Aaron Thompson, Jeffrey G. Catalano. The manuscript will be submitted to Geochimica et Cosmochimica Acta. This dataset contains sample characterization and oxidation kinetics results for two synthetic, Fe(II)-bearing trioctahedral smectites. Both clay minerals were suspended in media solution and then exposed to a series of oxidants: dissolved oxygen equilibrated with 21% O2, dissolved oxygen equilibrated with 2% O2, 5 mmol/L nitrite, or an excess of hydrogen peroxide. The post-reaction solids were characterized by powder X-ray diffraction and Mossbauer spectroscopy. The file "Kupper2022_XRD_data.csv" contains powder X-ray diffraction patterns of moderate-iron trioctahedral smectite [Ca0.17(FeII1.59Mg0.78FeIII0.12Al0.33)(Si3.58Al0.42)O10(OH)2] and high-iron trioctahedral smectite [Ca0.20(FeII2.16Mg0.26FeIII0.19Al0.24)(Si3.48Al0.52)O10(OH)2]. "Unaltered" indicates the initial, synthesized clays. The other labels indicate samples reacted with the specified oxidant: 21% O2, 2% O2, 5 mmol/L dissolved nitrite, and an excess of hydrogen peroxide (H2O2). These data appear in Figures 1, 5, and 6 in the associated manuscript. The folder "Kupper2022_Mossbauer_data" contains the Mossbauer spectra of moderate-iron trioctahedral smectite and high-iron trioctahedral smectite. "Unaltered" indicates the initial, synthesized clays. The other labels indicate samples reacted with the specified oxidant: 21% O2, 2% O2, 5 mmol/L dissolved nitrite, and an excess of hydrogen peroxide (H2O2). The subfolders labeled 295K, 13K, and 5K indicate the temperature in Kelvin at which data were collected. These data appears in Figures 2, 8, and 9 in the associated manuscript. The file "Kupper2022_OxidationKinetics_data.csv" contains data on solid phase Fe(II)/Total Fe in the moderate-iron trioctahedral smectite and high-iron trioctahedral smectite as a function of time in hours during reaction with 21%O2, 2%O2, or 5 mmol/L nitrite. Oxidation-free control data are also provided. These data appear in Figures 3, 4, and S3 in the associated manuscript. The file "Kupper2022_ModIron_Nitrite_data.csv" contains dissolved nitrite concentrations during the experiments with the moderate-iron smectite. These data appear in Figure S2 in the associated manuscript. The folder "Kupper2022_Oxygen_data" contains dissolved oxygen concentrations (in umol/L) and temperature as a function of time for the oxidation experiments with the moderate- and high-iron smectite reacted with 21% or 2% O2. These data appear in Figure S1 in the associated manuscript. The file "Kupper2022_EXAFS_data.csv" contains the XAFS spectra of the moderate- and high-iron smectites upon synthesis and after exposure to 21% O2 or H2O2.本数据集配套于手稿《三八面体蒙脱石中二价铁的氧化速率与产物》（*Rates and Products of Oxidation of Ferrous Iron in Trioctahedral Smectites*），作者为Robert J. Kupper、Nanqing Zhou、Clara S. Chan、Aaron Thompson、Jeffrey G. Catalano。该手稿将提交至《Geochimica et Cosmochimica Acta》（地质化学与宇宙化学学报）。本数据集包含两种合成的含二价铁三八面体蒙脱石的样品表征与氧化动力学结果。将这两种黏土矿物悬浮于介质溶液后，分别暴露于四种氧化剂：与21%氧气平衡的溶解氧、与2%氧气平衡的溶解氧、5 mmol/L亚硝酸盐，或过量过氧化氢。反应后的固体通过粉末X射线衍射（powder X-ray diffraction, PXRD）和穆斯堡尔光谱（Mössbauer spectroscopy）进行表征。 文件"Kupper2022_XRD_data.csv"包含中高铁三八面体蒙脱石[Ca₀.₁₇(FeII₁.₅₉Mg₀.₇₈FeIII₀.₁₂Al₀.₃₃)(Si₃.₅₈Al₀.₄₂)O₁₀(OH)₂]和高铁三八面体蒙脱石[Ca₀.₂₀(FeII₂.₁₆Mg₀.₂₆FeIII₀.₁₉Al₀.₂₄)(Si₃.₄₈Al₀.₅₂)O₁₀(OH)₂]的粉末X射线衍射图谱。其中"未处理"代表初始合成的黏土样品，其余标签代表经对应氧化剂处理后的样品：21% O₂、2% O₂、5 mmol/L溶解态亚硝酸盐及过量过氧化氢（H₂O₂）。该数据对应关联手稿中的图1、图5和图6。 文件夹"Kupper2022_Mossbauer_data"包含中高铁与高铁三八面体蒙脱石的穆斯堡尔光谱。其中"未处理"代表初始合成的黏土样品，其余标签代表经对应氧化剂处理后的样品：21% O₂、2% O₂、5 mmol/L溶解态亚硝酸盐及过量过氧化氢（H₂O₂）。以295K、13K和5K命名的子文件夹代表数据采集时的温度（单位：开尔文）。该数据对应关联手稿中的图2、图8和图9。 文件"Kupper2022_OxidationKinetics_data.csv"包含中高铁与高铁三八面体蒙脱石在与21% O₂、2% O₂或5 mmol/L亚硝酸盐反应过程中，固相Fe(II)/总Fe比值随反应时间（小时）的变化数据，同时提供了无氧化过程的对照组数据。该数据对应关联手稿中的图3、图4及补充材料图S3。 文件"Kupper2022_ModIron_Nitrite_data.csv"包含中高铁蒙脱石实验过程中的溶解态亚硝酸盐浓度数据，对应关联手稿中的补充材料图S2。 文件夹"Kupper2022_Oxygen_data"包含中高铁与高铁蒙脱石分别与21% O₂或2% O₂进行氧化实验时，溶解氧浓度（单位：μmol/L）及温度随反应时间的变化数据，对应关联手稿中的补充材料图S1。 文件"Kupper2022_EXAFS_data.csv"包含中高铁与高铁蒙脱石在合成后及暴露于21% O₂或H₂O₂后的X射线吸收精细结构（X-ray Absorption Fine Structure, XAFS）光谱。