TY - JOUR
T1 - Synthesis, Structure, and Magnetic Properties of an Fe36Dimethylarsinate Cluster
T2 - The Largest "ferric Wheel"
AU - Lee, Kenneth Hong Kit
AU - Aebersold, Lucas
AU - Peralta, Juan E.
AU - Abboud, Khalil A.
AU - Christou, George
N1 - Funding Information:
This work was supported by the U.S. National Science Foundation (NSF; Grant CHE-1900321) and by the Office of Basic Energy Sciences, U.S. Department of Energy, as part of the Computational Chemical Sciences Program under Award DE-SC0018331. We thank the NSF for funding of the X-ray diffractometer through Grant CHE-1828064. L.A. and J.E.P. acknowledge support from the Office of Basic Energy Sciences, U.S. Department of Energy (Grant DE-SC0005027).
Publisher Copyright:
© 2022 American Chemical Society. All rights reserved.
PY - 2022/10/31
Y1 - 2022/10/31
N2 - The synthesis and characterization of a high-nuclearity FeIII/O/arsinate cluster is reported within the salt [Fe36O12(OH)6(O2AsMe2)63(O2CH)3(H2O)6](NO3)12(1). The compound was prepared from the reaction of Fe(NO3)3·9H2O, dimethylarsinic acid (Me2AsO2H), and triethylamine in a 1:2:4 molar ratio in acetonitrile. The Fe36cation of 1 is an unprecedented structural type consisting of nine Fe4butterfly units of two types, three {FeIII4(μ3-O)2} units A, and six {FeIII4(μ3-O)(μ3-OH)} units B, linked by multiple bridging Me2AsO2-groups into an Fe36triangular wheel/loop with C3crystallographic and D3virtual symmetry that looks like a guitar plectrum. The unusual structure has been rationalized on the basis of the different curvatures of units A and B, the presence of intra-Fe36hydrogen bonding, and the tendency of Me2AsO2-groups to favor μ3-bridging modes. The cations stack into supramolecular nanotubes parallel to the crystallographic c axis and contain badly disordered solvent and NO3-anions. The cation of 1 is the highest-nuclearity "ferric wheel" to date and also the highest-nuclearity Fe/O cluster of any structural type with a single contiguous Fe/O core. Variable-temperature direct-current magnetic susceptibility data and alternating-current in-phase magnetic susceptibility data indicate that the cation of 1 possesses an S = 0 ground state and dominant antiferromagnetic interactions. The Fe2pairwise Ji,jcouplings were estimated by the combined use of a magnetostructural correlation for high-nuclearity FeIII/oxo clusters and density functional theory calculations using broken-symmetry methods and the Green's function approach. The three methods gave satisfyingly similar Ji,jvalues and allowed the identification of spin-frustration effects and the resulting relative spin-vector alignments and thus rationalization of the S = 0 ground state of the cation.
AB - The synthesis and characterization of a high-nuclearity FeIII/O/arsinate cluster is reported within the salt [Fe36O12(OH)6(O2AsMe2)63(O2CH)3(H2O)6](NO3)12(1). The compound was prepared from the reaction of Fe(NO3)3·9H2O, dimethylarsinic acid (Me2AsO2H), and triethylamine in a 1:2:4 molar ratio in acetonitrile. The Fe36cation of 1 is an unprecedented structural type consisting of nine Fe4butterfly units of two types, three {FeIII4(μ3-O)2} units A, and six {FeIII4(μ3-O)(μ3-OH)} units B, linked by multiple bridging Me2AsO2-groups into an Fe36triangular wheel/loop with C3crystallographic and D3virtual symmetry that looks like a guitar plectrum. The unusual structure has been rationalized on the basis of the different curvatures of units A and B, the presence of intra-Fe36hydrogen bonding, and the tendency of Me2AsO2-groups to favor μ3-bridging modes. The cations stack into supramolecular nanotubes parallel to the crystallographic c axis and contain badly disordered solvent and NO3-anions. The cation of 1 is the highest-nuclearity "ferric wheel" to date and also the highest-nuclearity Fe/O cluster of any structural type with a single contiguous Fe/O core. Variable-temperature direct-current magnetic susceptibility data and alternating-current in-phase magnetic susceptibility data indicate that the cation of 1 possesses an S = 0 ground state and dominant antiferromagnetic interactions. The Fe2pairwise Ji,jcouplings were estimated by the combined use of a magnetostructural correlation for high-nuclearity FeIII/oxo clusters and density functional theory calculations using broken-symmetry methods and the Green's function approach. The three methods gave satisfyingly similar Ji,jvalues and allowed the identification of spin-frustration effects and the resulting relative spin-vector alignments and thus rationalization of the S = 0 ground state of the cation.
UR - http://www.scopus.com/inward/record.url?scp=85140298432&partnerID=8YFLogxK
U2 - 10.1021/acs.inorgchem.2c02841
DO - 10.1021/acs.inorgchem.2c02841
M3 - Article
C2 - 36251497
AN - SCOPUS:85140298432
SN - 0020-1669
VL - 61
SP - 17256
EP - 17267
JO - Inorganic Chemistry
JF - Inorganic Chemistry
IS - 43
ER -