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Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
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TM7TM'6B8 (TM = Ta, Nb; TM' = Ru, Rh, Ir): new compounds with [B6] ring polyanions
Qiang Zheng1, Miroslav Kohout, Roman Gumeniuk
1Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Str. 40, 01187 Dresden, Germany.
Inorganic Chemistry
|June 26, 2012
Summary
New ternary boron compounds, TM(7)TM'(6)B(8), were synthesized and analyzed. Their unique polyanionic structures ([B(6)] and [TM'(6)B(2)]) and metallic magnetic properties were revealed through advanced bonding and band structure studies.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Computational Materials Science
Background:
- Ternary boron compounds offer unique structural and electronic properties.
- Understanding chemical bonding in complex inorganic materials is crucial for predicting their behavior.
Purpose of the Study:
- To synthesize and characterize novel ternary boron compounds of the formula TM(7)TM'(6)B(8).
- To investigate the intricate chemical bonding within these compounds.
- To correlate bonding characteristics with observed magnetic properties.
Main Methods:
- High-temperature thermal treatment of elemental mixtures.
- Electron density/electron localizability (ED/EL) approach for chemical bonding analysis.
- Band structure calculations.
Main Results:
- Successful synthesis of TM(7)TM'(6)B(8) compounds (TM = Ta, Nb; TM' = Ru, Rh, Ir).
- Identification of covalently bonded polyanions [B(6)] and [TM'(6)B(2)] and separated TM cations.
- All compounds exhibit metallic Pauli-paramagnetic (TM' = Ru, Rh) or diamagnetic (TM' = Ir) behavior, consistent with calculations.
Conclusions:
- The ED/EL approach effectively elucidates bonding in these complex borides.
- The structural and electronic properties are strongly influenced by the interplay between polyanionic boron frameworks and metallic components.
- These findings contribute to the understanding of structure-property relationships in novel refractory materials.
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