Video Experimental Relacionado
Updated: Dec 25, 2025
09:30
Author Spotlight: Exploring Cellular Processes by Modeling Ligands in Cryo-EM Maps
Published on: July 19, 2024
1.9K
Diferencias críticas en la estructura atómica 3D de los nanocristales protegidos por ligandos individuales en
Byung Hyo Kim1,2, Junyoung Heo1,2, Sungin Kim1,2
1Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea.
Science (New York, N.Y.)
|April 4, 2020
Resumen
La comprensión de las estructuras nanocristalinas individuales es clave para predecir las propiedades. La nueva microscopía electrónica 3D revela variaciones significativas en los nanocristales de platino, que afectan sus características fundamentales.
Área de la Ciencia:
- Ciencias de los materiales
- Nanotecnología
- Química
Sus antecedentes:
- La determinación precisa de la estructura atómica tridimensional (3D) de los nanocristales individuales es esencial para comprender sus propiedades físicas.
- Los nanocristales del mismo lote exhiben variaciones de tamaño, distorsiones de celosía y defectos.
Objetivo del estudio:
- Para revelar la heterogeneidad intrínseca en los nanocristales de platino protegidos por ligando en solución.
- Comprender cómo las diferencias estructurales afectan a las propiedades y aplicaciones de los nanocristales.
Principales métodos:
- Desarrollo de la microscopía electrónica de células líquidas 3D de resolución atómica.
- Caracterización estructural de los nanocristales coloidales individuales de platino en solución.
Principales resultados:
- Reveló una heterogeneidad intrínseca crítica en los nanocristales de platino.
- Se han identificado degeneraciones estructurales, desviaciones en los parámetros de la celosía, defectos internos y tensión.
- Demostró que las diferencias estructurales contribuyen significativamente a las energías libres.
Conclusiones:
- La heterogeneidad estructural intrínseca en los nanocristales es significativa y debe considerarse.
- El análisis estructural 3D de resolución atómica es crucial para predecir las propiedades y aplicaciones de los nanocristales.
Videos de Conceptos Relacionados
02:58Crystal Field Theory - Octahedral Complexes
30.1K
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
30.1K
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
47.5K
Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
47.5K
02:42Ionic Crystal Structures
16.6K
Ionic crystals consist of two or more different kinds of ions that usually have different sizes. The packing of these ions into a crystal structure is more complex than the packing of metal atoms that are the same size.
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
16.6K
02:51Metal-Ligand Bonds
23.5K
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
23.5K
02:40Ligand Binding Sites
14.7K
Proteins are dynamic macromolecules that carry out a wide variety of essential processes; however, the activities of most proteins depend on their interactions with other molecules or ions, known as ligands.
Protein-ligand interactions are quite specific; even though numerous potential ligands surround a cellular protein at any given time, only a particular ligand can bind to that protein. Moreover, a ligand binds only to a dedicated area on the surface of the protein, known as the...
Protein-ligand interactions are quite specific; even though numerous potential ligands surround a cellular protein at any given time, only a particular ligand can bind to that protein. Moreover, a ligand binds only to a dedicated area on the surface of the protein, known as the...
14.7K
01:19Complexation Equilibria: The Chelate Effect
1.0K
In complexation reactions, metal atoms or cations interact with ligands to form donor-acceptor adducts called metal complexes. Ligands that bind through one donor site are monodentate, ligands with two donor sites are bidentate, and those with more than two donor sites are polydentate ligands. For example, ethylene diamine is a bidentate ligand that binds through two nitrogen donor atoms, forming a five-membered ring. EDTA is a polydentate ligand that binds through four oxygen and two nitrogen...
1.0K