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Updated: Aug 3, 2026
10:42
Combining Solid-state and Solution-based Techniques: Synthesis and Reactivity of Chalcogenidoplumbates(II or IV)
Published on: December 29, 2016
Experimental versus expected halide-ion size differences; structural changes in three series of isotypic bismuth
1Kristallographisches Institut der Universität Freiburg, Hermann-Herder-Strasse 5, D-79104 Freiburg, Germany. egbert.keller@krist.uni-freiburg.de
Summary
Comparing bismuth chalcogenide halide compounds revealed significant deviations in halide-ion sizes. These differences are attributed to steric strain and structural complexities within the KBi(6)O(9)X, BiOX, and BiSX series.
Area of Science:
- Inorganic Chemistry
- Solid-State Chemistry
- Crystallography
Background:
- Bismuth chalcogenide halides are a class of compounds with potential applications in materials science.
- Understanding the structural variations within these compounds is crucial for predicting their properties.
- Previous studies have explored various bismuth-based materials, but systematic comparisons of halide-ion size effects are less common.
Purpose of the Study:
- To compare experimentally determined halide-ion sizes with theoretical expectations in three series of bismuth chalcogenide halides.
- To investigate the factors causing deviations from expected size differences, including steric strain and structural features.
- To analyze structural changes and discuss isotypism within the BiOX and BiSX series.
Main Methods:
- Experimental determination of halide-ion sizes in KBi(6)O(9)X, BiOX, and BiSX compounds.
- Comparison of experimental data with theoretical size difference predictions.
- Analysis of structural data, including bond-valence patterns, anion-anion repulsion, and connectivity schemes.
- Examination of specific structural features in BiOF and structural evolution in BiSX series.
Main Results:
- Significant deviations were observed between experimentally determined and expected halide-ion size differences across all three compound series.
- Steric strain arising from heterogeneous bond-valence patterns was identified as a primary cause for these deviations.
- Anion-anion repulsion and changes in connectivity schemes were found to influence halide-ion sizes in the BiOX series.
- Distinct structural features were noted for BiOF, and structural variations were analyzed within the BiSX series.
Conclusions:
- The study highlights the significant impact of steric strain and structural factors on halide-ion sizes in bismuth chalcogenide halides.
- Deviations from expected sizes are not random but are systematically linked to specific structural characteristics.
- The concept of isotypism within the BiOX series requires careful consideration due to observed structural variations.
- Further research into these structure-property relationships could lead to the design of novel bismuth-based materials.
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