次锰酸盐 - 维基百科,自由的百科全书
次锰酸盐 | |
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英文名 | Hypomanganate |
别名 | 锰(V)酸盐 |
识别 | |
CAS号 | 14333-15-4 ![]() |
性质 | |
化学式 | MnO3− 4 |
摩尔质量 | 118.94 g·mol⁻¹ |
若非注明,所有数据均出自标准状态(25 ℃,100 kPa)下。 |
次锰酸根,又称锰(V)酸根,是一种锰的含氧酸根,化学式 MnO3−
4,次锰酸盐则是这种阴离子形成的盐。
次锰酸盐通常是亮蓝色的。[1][2]最著名的次锰酸盐是次锰酸钾 K
3MnO
4,但次锰酸钠 Na
3MnO
4、次锰酸钡 Ba
3(MnO
4)
2和钾钡盐 KBaMnO
4都是已知的。[3]在磷灰石[4][5]和钙铁铝石[6]的人造变种中,次锰酸根可以取代其中的磷酸根 PO3−
4。
历史
[编辑]次锰酸根于1946年由Hermann Lux首次报告。他通过氧化钠 Na
2O、二氧化锰 MnO
2和亚硝酸钠 NaNO
2在500 °C的反应,得到了亮蓝色的次锰酸钠。[7][3]他也从其氢氧化钠溶液结晶出了十水合物 Na
3MnO
4·10H
2O。
结构和性质
[编辑]次锰酸根是四面体形的含氧酸根,结构类似硫酸根、锰酸根和高锰酸根。作为d2电子构型的四面体形分子,它在基态下为三线态。[3]
次锰酸根呈亮蓝色,[1]最大吸收光谱λmax = 670 nm(ε = 900 dm3 mol−1 cm−1)。[8][9]
稳定性
[编辑]次锰酸盐不稳定,会歧化成锰酸盐和二氧化锰。[10][1]在pH 14下,次锰酸盐预测的电极电势如下:[11][12][13]
- MnO2−
4 + e− ⇌ MnO3−
4 E = +0.27 V - MnO3−
4 + e− + 2 H2O ⇌ MnO2 + 4 OH− E = +0.96 V
然而,歧化反应在强碱性环境下(OH−浓度超过5–10 mol/L)会变慢。[1][7]
这个歧化反应被认为有质子化的中间体 HMnO2−
4。[13]它在反应 HMnO2−
4 ⇌ MnO3−
4 + H+中的pKa为13.7 ± 0.2。[14]然而,K3MnO4已经和Ca2Cl(PO4)共结晶,使人们可以研究次锰酸根的紫外-可见分光光度法。[10][15]
制备
[编辑]次锰酸盐可以由亚硫酸盐、[1]过氧化氢[16]或扁桃酸[9]小心还原锰酸盐而成。
用处
[编辑]氟化钒酸锶 Sr
5(VO
4)
3F中的一些钒酸根被次锰酸根取代后,可能可用于近红外激光器中。[17]
次锰酸钡 Ba
3(MnO
4)
2有有趣的磁性性质。[18]
相关化合物
[编辑]次锰酸根的共轭酸次锰酸 H
3MnO
4因为会迅速歧化而无法制备,但其第三酸度系数已通过脉冲辐解技术估计:[14]
- HMnO2−
4 ⇌ MnO3−
4 + H+ pKa = 13.7 ± 0.2
参见
[编辑]参考资料
[编辑]- ^ 1.0 1.1 1.2 1.3 1.4 Greenwood, Norman N.; Earnshaw, A. Chemistry of the Elements. Oxford: Pergamon. 1984: 1221–22. ISBN 0-08-022057-6..
- ^ Reinen, D.; Rauw, W.; Kesper, U.; Atanasov, M.; Güdel, H.U.; Hazenkamp, M.; Oetliker, U. Colour, luminescence and bonding properties of tetrahedrally coordinated chromium(IV), manganese(V) and iron(VI) in various oxide ceramics. Journal of Alloys and Compounds (Elsevier BV). 1997, 246 (1-2): 193–208. ISSN 0925-8388. doi:10.1016/s0925-8388(96)02461-9.
- ^ 3.0 3.1 3.2 zur Loye, K. D.; Chance, W. M.; Yeon, J.; zur Loye, H.-C. Synthesis, Crystal Structure, and Magnetic Properties of the Oxometallates KBaMnO4 and KBaAsO4. Solid State Sciences. 2014, 37: 86–90. Bibcode:2014SSSci..37...86Z. doi:10.1016/j.solidstatesciences.2014.08.013
.
- ^ Dardenne, K.; Vivien, D.; Huguenin, D. Color of Mn(V)-Substituted Apatites A10((B, Mn)O4)6F2, A=Ba, Sr, Ca; B=P, V. Journal of Solid State Chemistry (Elsevier BV). 1999, 146 (2): 464–472. ISSN 0022-4596. doi:10.1006/jssc.1999.8394.
- ^ Grisafe, D.A.; Hummel, F.A. Pentavalent ion substitutions in the apatite structure part A. Crystal chemistry. Journal of Solid State Chemistry (Elsevier BV). 1970, 2 (2): 160–166. ISSN 0022-4596. doi:10.1016/0022-4596(70)90064-2.
- ^ Jiang, Peng; Li, Jun; Ozarowski, A.; Sleight, Arthur W.; Subramanian, M. A. Intense Turquoise and Green Colors in Brownmillerite-Type Oxides Based on Mn5+ in Ba2In2–xMnxO5+x. Inorganic Chemistry (American Chemical Society (ACS)). 2013-01-18, 52 (3): 1349–1357. ISSN 0020-1669. doi:10.1021/ic3020332.
- ^ 7.0 7.1 Herrman Lux (1946): "Über Salze des fünfwertigen Mangans (页面存档备份,存于互联网档案馆)." Zeitschrift für Naturforschung, volume 1, pages 281-283.
- ^ Carrington, A.; Symons, M. C. R., Structure and reactivity of the oxy-anions of transition metals. Part I. The manganese oxy-anions, J. Chem. Soc., 1956: 3373–80, doi:10.1039/JR9560003373
- ^ 9.0 9.1 9.2 Lee, Donald G.; Chen, Tao, Reduction of manganate(VI) by mandelic acid and its significance for development of a general mechanism of oxidation of organic compounds by high-valent transition metal oxides, J. Am. Chem. Soc., 1993, 115 (24): 11231–36, doi:10.1021/ja00077a023.
- ^ 10.0 10.1 Cotton, F. Albert; Wilkinson, Geoffrey, Advanced Inorganic Chemistry 4th, New York: Wiley: 746, 1980, ISBN 0-471-02775-8.
- ^ Weast, Robert C. (编). CRC Handbook of Chemistry and Physics 62nd. Boca Raton, FL: CRC Press. 1981: D-134. ISBN 0-8493-0462-8..
- ^ Manganese – compounds – standard reduction potentials, WebElements, [2010-06-26], (原始内容存档于2021-01-17).
- ^ 13.0 13.1 Sekula-Brzezińska, K.; Wrona, P. K.; Galus, Z., Rate of the MnO4−/MnO42− and MnO42−/MnO43− electrode reactions in alkaline solutions at solid electrodes, Electrochim. Acta, 1979, 24 (5): 555–63, doi:10.1016/0013-4686(79)85032-X.
- ^ 14.0 14.1 Rush, J. D.; Bielski, B. H. J., Studies of Manganate(V), -(VI), and -(VII) Tetraoxyanions by Pulse Radiolysis. Optical Spectra of Protonated Forms, Inorg. Chem., 1995, 34 (23): 5832–38, doi:10.1021/ic00127a022.
- ^ Carrington, A.; Symons, M. C. R., Structure and reactivity of the oxy-anions of transition metals. Part I. The manganese oxy-anions, J. Chem. Soc., 1956: 3373–80, doi:10.1039/JR9560003373.
- ^ Lee, Donald G.; Chen, Tao, Oxidation of hydrocarbons. 18. Mechanism of the reaction between permanganate and carbon-carbon double bonds, J. Am. Chem. Soc., 1989, 111 (19): 7534–38, doi:10.1021/ja00201a039.
- ^ Merkle, Larry D.; Guyot, Yannick; Chai, Bruce H. T. Spectroscopic and laser investigations of Mn5+:Sr5(VO4)3F. Journal of Applied Physics (AIP Publishing). 1995-01-15, 77 (2): 474–480. ISSN 0021-8979. doi:10.1063/1.359585.
- ^ Stone, M. B.; Lumsden, M. D.; Qiu, Y.; Samulon, E. C.; Batista, C. D.; Fisher, I. R. Dispersive magnetic excitations in theS=1antiferromagnetBa3Mn2O8. Physical Review B (American Physical Society (APS)). 2008-04-02, 77 (13). ISSN 1098-0121. doi:10.1103/physrevb.77.134406.
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