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A comprehensive crystallographic study is presented of the complete series of rare-earth(III) chloride hydrates. Early lanthanides form dimeric [(H2O)7RE(μ-Cl)2RE(H2O)7]4+binuclear complexes in which eachREatom (RE= La3+, Ce3+) is coordinated by seven H2O molecules and two bridging inner-sphere chloride ions. Di-μ-chlorido-bis[heptaaqualanthanide(III)] tetrachloride, [(H2O)7RE(μ-Cl)2RE(H2O)7]Cl4, crystallizes in the triclinic space groupP1. Heavier lanthanides exhibit monomeric [RECl2(H2O)6]+units where eachREatom (RE= Pr3+, Nd3+, Sm3+–Lu3+) is coordinated by six H2O molecules and two inner-sphere chloride ions. Hexaaquadichloridolanthanide(III) chlorides, [RECl2(H2O)6]Cl, adopt the monoclinic space groupP2/c.In both structures, the cationicinner-spherecomplex is counter-charged by the corresponding number ofouter-sphereCl−anions, in which the metal ion and outer-sphere chloride ion lie on crystallographic twofold axes. Crystal structures for all compounds were determined in high quality with refined H-atom positions and were collected at the same temperature (100 K), providing a uniform structural dataset and addressing discrepancies in previous reports. The crystal structure of [HoCl2(H2O)6]Cl is reported for the first time.
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Flux Growth of La 3 MC 2 ( M = Sb, Bi, Te), a New Family of Ternary Carbides
Reactions of carbon with a heavy main group metal (M = Sb, Bi, or Te) in an excess of lanthanum/nickel eutectic flux lead to formation of a family of carbide compounds La3MC2with a new structure type. The monoclinic structure features C24−anions octahedrally coordinated by six La3+cations, andManions surrounded by 8 La3+cations. These compounds are not charge‐balanced and lie on the border between intermetallic carbides and mixed anion salts. Density of states calculations show a pseudogap at the Fermi level for La3BiC2, which indicates that this compound is a poor metal with optimized LaBi bonding interactions.
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- Award ID(s):
- 2126077
- PAR ID:
- 10653237
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Zeitschrift für anorganische und allgemeine Chemie
- Volume:
- 651
- Issue:
- 10
- ISSN:
- 0044-2313
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/zaac.202500046
