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  • Mixed‐Valence Manganese Carboxylate Clusters, {Mn III 6 Mn II 4 }, {Mn III 7 Mn II 5 Na}, and {Mn III 7 Mn II 5 }, Derived from the Combined Use of Di‐2‐pyridyl Ketone with Selected Aliphatic Diols
Title: Mixed‐Valence Manganese Carboxylate Clusters, {Mn III 6 Mn II 4 }, {Mn III 7 Mn II 5 Na}, and {Mn III 7 Mn II 5 }, Derived from the Combined Use of Di‐2‐pyridyl Ketone with Selected Aliphatic Diols
Abstract

Three new polynuclear clusters with the formulae [Mn10O4(OH)(OMe){(py)2C(O)2}2{(py)2C(OMe)(O)}4(MeCO2)6](ClO4)2(1), Na[Mn12O2(OH)3(OMe){(py)2C(O)2}6{(py)2C(OH)(O)}2(MeCO2)2(H2O)10](ClO4)8(2) and [Mn12O4(OH)2{(py)2C(O)2}6{(py)2C(OMe)(O)}(MeCO2)3(NO3)3(H2O)(DMF)2](NO3)2(3) were prepared from the combination of di‐2‐pyridyl ketone, (py)2CO, with the aliphatic diols (1,3‐propanediol (pdH2) or 1,4‐butanediol (1,4‐bdH2)) in Mn carboxylate chemistry. The reported compounds do not include the aliphatic diols employed in this reaction scheme; however, their use is essential for the formation of1–3. The crystal structures of1–3are based on multilayer cores which, to our knowledge, are reported for the first time in Mn cluster chemistry. Direct current (dc) magnetic susceptibility studies showed the presence of dominant antiferromagnetic exchange interactions within1–3. Alternating current (ac) magnetic susceptibility studies revealed the presence of out‐of‐phase signals below 3.0 K for2and3indicating the slow relaxation of the magnetization vector, characteristic of single‐molecule magnets; theUeffvalue of2was found to be 23 K and the preexponential factorτ0~7.6×10−9 s.

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NSF-PAR ID:
10489852
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
European Journal of Inorganic Chemistry
Volume:
27
Issue:
12
ISSN:
1434-1948
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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