Ultra‐small nanoparticles of CeO2obtained in molecular form, so‐called molecular nanoparticles, have been limited to date to a family whose largest member is of nuclearity Ce40with a {Ce40O58} core atom count. Herein we report that a synthetic procedure has been developed to the cation [Ce100O149(OH)18(O2CPh)60(PhCO2H)12(H2O)20]16+, a member with a much higher Ce100nuclearity and a {Ce100O167} core that is more akin to the smallest ceria nanoparticles. Its crystal structure reveals it to possess a 2.4 nm size and high D2dsymmetry, and it has also allowed identification of core surface features including facet composition, the presence and location of Ce3+and H+(i.e. HO−) ions, and the binding modes of the ligand monolayer of benzoate, benzoic acid, and water ligands.
- Award ID(s):
- 1900321
- NSF-PAR ID:
- 10349326
- Date Published:
- Journal Name:
- Dalton Transactions
- Volume:
- 50
- Issue:
- 43
- ISSN:
- 1477-9226
- Page Range / eLocation ID:
- 15524 to 15532
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract -
Abstract Ultra‐small nanoparticles of CeO2obtained in molecular form, so‐called molecular nanoparticles, have been limited to date to a family whose largest member is of nuclearity Ce40with a {Ce40O58} core atom count. Herein we report that a synthetic procedure has been developed to the cation [Ce100O149(OH)18(O2CPh)60(PhCO2H)12(H2O)20]16+, a member with a much higher Ce100nuclearity and a {Ce100O167} core that is more akin to the smallest ceria nanoparticles. Its crystal structure reveals it to possess a 2.4 nm size and high D2dsymmetry, and it has also allowed identification of core surface features including facet composition, the presence and location of Ce3+and H+(i.e. HO−) ions, and the binding modes of the ligand monolayer of benzoate, benzoic acid, and water ligands.
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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 –3 are 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 for2 and3 indicating the slow relaxation of the magnetization vector, characteristic of single‐molecule magnets; theUeff value of2 was found to be 23 K and the preexponential factorτ0 ~7.6×10−9 s. -
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