Video Experimental Relacionado
Updated: Jul 26, 2026
11:00
Hand Controlled Manipulation of Single Molecules via a Scanning Probe Microscope with a 3D Virtual Reality Interface
Published on: October 2, 2016
Rotación de una sola molécula dentro de un cojinete supramolecular
Gimzewski1, Joachim, Schlittler
1J. K. Gimzewski, R. R. Schlittler, V. Langlais, IBM Research Division, Zurich Research Laboratory, Saumerstrasse 4, 8803 Ruschlikon, Switzerland. C. Joachim and H. Tang, CEMES-CNRS, 29 rue J. Marvig, Boite Postale 4347, 31055 Toulouse.
Science (New York, N.Y.)
|July 24, 1998
Resumen
Los investigadores visualizan un rotor de una sola molécula en una dirección supramolecular. El rotor existe en estados rotativos o inmovilizados, con barreras de energía de rotación que difieren significativamente de la energía térmica a temperatura ambiente.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Nanotecnología La nanotecnología es la nanotecnología.
- Química Física es la química física.
Sus antecedentes:
- Las máquinas de una sola molécula son cruciales para la nanotecnología.
- Comprender el movimiento molecular es clave para diseñar nanomateriales funcionales.
Objetivo del estudio:
- Para visualizar y verificar experimentalmente el funcionamiento de un rotor de una sola molécula dentro de un rodamiento supramolecular.
- Para caracterizar los distintos estados y paisajes energéticos que rigen la rotación molecular.
Principales métodos:
- Utilizó microscopía de túnel de barrido (STM) para imágenes de alta resolución de moléculas individuales.
- Las moléculas observadas se encuentran en dos estados definidos espacialmente, separados por 0,26 nm.
- Realizó cálculos para determinar la barrera de energía para la rotación en cada estado.
Principales resultados:
- Se visualizó con éxito un rotor de una sola molécula que funciona dentro de un rango supramolecular.
- Identificó dos estados distintos: un estado giratorio y un estado inmovilizado.
- Calculó las barreras energéticas, encontrándolas por debajo de la energía térmica para la rotación y por encima de ella para la inmovilización a temperatura ambiente.
Conclusiones:
- El estudio proporciona evidencia experimental para la rotación controlada de una sola molécula en un entorno supramolecular diseñado.
- Los estados observados y las barreras de energía resaltan el potencial de un control preciso sobre el movimiento molecular.
- Este trabajo sienta las bases para el desarrollo de sofisticadas máquinas y dispositivos moleculares.
Videos de Conceptos Relacionados
02:06Newman Projections
Different notations are used to represent the three-dimensional structure of molecules on two-dimensional surfaces. One of the most commonly used representations is the dash-wedge formula. The dashed wedges, solid wedges, and the plane lines indicate the groups situated behind the plane, coming out of the plane, and in the plane, respectively.
The organic molecules rotate across the single bonds leading to numerous temporary three-dimensional structures of varying energy known as conformers.
The organic molecules rotate across the single bonds leading to numerous temporary three-dimensional structures of varying energy known as conformers.
02:25Molecules with Multiple Chiral Centers
Molecules that possess multiple chiral centers can afford a large number of stereoisomers. For instance, while some molecules like 2-butanol have one chiral center, defined as a tetrahedral carbon atom with four different substituents attached, several molecules like butane-2,3-diol have multiple chiral centers. A simple formula to predict the number of stereoisomers possible for a molecule with n chiral centers is 2n. However, there can be a lower number where some of the stereoisomers are...
02:18Fischer Projections
Learning to draw Fischer projections of molecules and understanding their relevance plays a crucial role in the visual depiction of organic molecules. A Fischer projection is a two-dimensional projection on a planar surface to simplify the three-dimensional wedge–dash representation of molecules. This is especially helpful in the case of molecules with multiple chiral centers that can be difficult to draw. Here, all the bonds of interest are represented as horizontal or vertical lines. While...
02:33Stereoisomerism of Cyclic Compounds
In this lesson, we delve into the role of ring conformation and its stability, which determines the spatial arrangement and, consequently, the molecular symmetry and stereoisomerism of cyclic compounds. 1,2-Dimethylcyclohexane is used as a case study to evaluate the possible number of stereoisomers. Here, given the multiple (n = 2) chiral centers, there are 2n = 4 possible configurations that lack a plane of symmetry, as the ring skeleton exists in a non-planar chair conformation. In addition,...
02:05Prochirality
The concept of prochirality leads to the nomenclature of the individual faces of a molecule and plays a crucial role in the enantioselective reaction. It is a concept where two or more achiral molecules react to produce chiral products. A typical process is the reaction of an achiral ketone to generate a chiral alcohol. Here, the achiral reactant reacts with an achiral reducing agent, sodium borohydride, to generate an equimolar mixture of the chiral enantiomers of the product. For example, an...
00:52¹H NMR of Conformationally Flexible Molecules: Temporal Resolution
At room temperature, the chair conformer of cyclohexane undergoes rapid ring flipping between two equivalent chair conformers at a rate of approximately 105 times per second. These two chair conformers are in equilibrium. The rapid ring flipping results in the interconversion of the axial proton to an equatorial proton and an equatorial to the axial proton. Such interconversions are too rapid and cannot be detected on the NMR timescale. Hence, the NMR spectrometer cannot distinguish between the...