6533b7d9fe1ef96bd126d56d

RESEARCH PRODUCT

Unprecedented multiple electronic spin transition in hepta- and nonanuclear complex compounds observed by Mössbauer spectroscopy

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Abstract The precursor [Fe(III)(5L)Cl](5LH2 = N,N′-bis(1-hydroxy-2- benzyliden)-1,7-diamino-4-azaheptane) is a high-spin (S = 5/2) complex. This precursor combined with the bridging units [Fe(II)(CN)6]4−, [Co(III)(CN)6]3−, and [Mo(CN)8]4− yields starshaped hepta- and nonanuclear clusters, [Fe(II){(CN)Fe(III)(5L)}6]Cl2, [Co(III){(CN)Fe(III)(5L)}6]Cl3 and [Mo(IV){(CN)Fe(III)(5L)}8]Cl4. The starshaped compounds are high-spin systems at room temperature. On cooling to 20 K some of the iron(III) centers in the Co(III)- and Mo(IV)-star switch to the low-spin state as proven by Mossbauer spectroscopy, i.e., multiple electronic transitions, while the Fe(II)-star remains in the high-spin state.