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In page Manganese:

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In Mn(CH3)2(dmpe)2, Mn(II) is low spin, which contrasts with the high spin character of its precursor, MnBr2(dmpe)2 (dmpe = (CH3)2PCH2CH2P(CH3)2).[2] Polyalkyl and polyaryl derivatives of manganese often exist in higher oxidation states, reflecting the electron-releasing properties of alkyl and aryl ligands. One example is [Mn(CH3)6]2−.[citation needed]