Four new three-dimensional (3-D) coordination frameworks based on the heptacyanomolybdate( iii ) anion were prepared and characterised by magnetic measurements: {[Mn II (imH) 2 ] 2 [Mn II (H 2 O)(imH) 3 ][Mn II (imH) 4 ] [Mo III (CN) 7 ] 2 ·6H 2 O} n ( 1 ) (imH = imidazole), {[Mn II (H 2 O) 2 (imH)] 3 [Mn II (H 2 O)(imH) 2 ][Mo III (CN) 7 ] 2 ·5H 2 O} n ( 2 ), {[Mn II (Htrz)(H 2 O) 2 ][Mn II (Htrz) 0.7 (H 2 O) 2.3 ][Mo III (CN) 7 ]·5.6H 2 O} n ( 3 ) (Htrz = 1,2,4-triazole) and {[Mn II (H 2 O) 2 ] 3 [Mn II (H 2 O) 4 ][Mo III (CN) 7 ] 2 ·6H 2 O·2urea} n ( 4 ). All four compounds exhibit long-range ferrimagnetic ordering and exhibit an opening of their magnetic hysteresis loops at 1.8 K; 1 and 2 exhibit the highest coercive fields among all known [Mo III (CN) 7 ]-based assemblies, 5000 and 4500 Oe respectively. The coercivity of 1–4 is correlated with the geometry of the heptacyanomolybdate( iii ) anion and the cyanide bridging pattern. A paramagnetic analogue of compound 1 , {[Mn II (imH) 2 ] 2 [Mn II (H 2 O)(imH) 3 ][Mn II (imH) 4 ][Re III (CN) 7 ] 2 ·6H 2 O} n ( 1Re ), where the heptacyanomolybdate( iii ) anion is substituted by the diamagnetic heptacyanorhenate( iii ) anion is also reported which constitutes the first example of a coordination framework based on [Re III (CN) 7 ] 4− .
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Sulfur K-Edge X-ray Absorption Spectroscopy and Density Functional Theory Calculations on Monooxo Mo IV and Bisoxo Mo VI Bis-dithiolenes: Insights into the Mechanism of Oxo Transfer in Sulfite Oxidase and Its Relation to the Mechanism of DMSO Reductase
- PAR ID:
- 10012777
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- Journal of the American Chemical Society
- Volume:
- 136
- Issue:
- 25
- ISSN:
- 0002-7863
- Page Range / eLocation ID:
- 9094 to 9105
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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