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Comentario sobre "Observación de complejos de tierra alcalina M ((CO) 8 (M = Ca, Sr o Ba) que imitan los metales de
Clark R Landis1, Russell P Hughes2, Frank Weinhold3
1Department of Chemistry, University of Wisconsin, Madison, WI 53706, USA. landis@chem.wisc.edu.
Science (New York, N.Y.)
|August 10, 2019
Resumen
Los octacarbonilos de metales alcalinos como el calcio, el estroncio y el bario no imitan la unión de metales de transición. El estudio refuta las afirmaciones basadas en métodos de análisis de descomposición energética defectuosos.
Área de la Ciencia:
- Química inorgánica
- Química Cuántica
- Ciencias de los materiales
Sus antecedentes:
- Estudios recientes propusieron que los compuestos octacarbonílicos de metales de tierra alcalina (Ca, Sr, Ba) exhiben un enlace similar al de los metales de transición.
- Este motivo de enlace de Dewar-Chatt-Duncanson propuesto en estos compuestos metálicos del grupo principal desafía los principios químicos establecidos.
Objetivo del estudio:
- Evaluar críticamente la afirmación de que los octacarbonilos de Ca, Sr y Ba imitan el motivo de enlace Dewar-Chatt-Duncanson.
- Identificar la fuente de la discrepancia entre la declaración y la comprensión química conocida.
Principales métodos:
- Análisis de los análisis de descomposición energética (EDA) comunicados.
- Examen de las distribuciones de densidad de electrones calculadas.
- Comparación con los principios establecidos de la unión química.
Principales resultados:
- Se demuestra que la pretendida imitación del motivo de unión Dewar-Chatt-Duncanson no tiene fundamento.
- Los análisis de descomposición energética utilizados en el estudio original se basan en un estado de referencia defectuoso.
- Las distribuciones de densidad de electrones calculadas no apoyan el modelo de enlace propuesto.
Conclusiones:
- Los octacarbonilos de Ca, Sr y Ba no muestran el clásico motivo de enlace Dewar-Chatt-Duncanson.
- Las conclusiones erróneas se derivan de un enfoque teórico fundamentalmente defectuoso en el estudio de referencia.
- Es necesaria una reevaluación de la unión en los carbonilos metálicos del grupo principal basada en métodos teóricos sólidos.
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