在光离子化甘氨酸中,超快的质子转移是通过混合量子-经典和量子动态的量子动态来实现的
Kossi Kety1, Jesús González-Vázquez2, Piero Decleva3
1Univ Gustave Eiffel, Univ Paris Est Creteil, CNRS, UMR 8208, MSME, F-77454 Marne-la-Vallée, France.
The Journal of chemical physics
|October 28, 2025
概括
研究了在电离型甘氨酸中超快的气转移. 电子连贯性迅速消散,导致质子转移主要到阴离子基本状态.
科学领域:
- 理论化学 理论化学
- 量子动力学 量子动力学是什么?
- 分子物理学 分子物理学
背景情况:
- 在实验中观察到甘氨酸分子的电离和随后的超快速分子内转移.
- 激发XUV时秒脉冲列车的激发会产生电子状态的叠加,与核动力学相结合.
研究的目的:
- 理论上研究在电离型甘氨酸中超快速的分子内转移.
- 分析电子连贯性和合电子核动力学的作用.
- 确定转移的条件和机制.
主要方法:
- 静态交换限制活性空间密度函数理论 (SEX-RAS-DFT) 对于电离概率.
- 多层多配置时间依赖的哈特树 (ML-MCTDH) 用于量子动力学模拟.
- 轨迹表面跳跃 (TSH) 对于长期合的电子核动力学.
主要成果:
- 在实验脉冲条件下,电子连贯性迅速消散 (<3 fs).
- 从单个电子状态开始的模拟准确地捕获动态.
- 转移主要发生在系统达到阴离子基本状态时.
结论:
- 电子连贯的快速消散简化了单态演变的动态.
- 质子转移是电离型甘氨酸中转移的主要机制.
- 理论发现为分子电离后的超快动态提供了洞察力.
相关概念视频
Protein Dynamics in Living Cells
2.6K
Different fluorescence-based techniques are used to study the protein dynamics in living cells. These techniques include FRAP, FRET, and PET.
Fluorescent recovery after photobleaching (FRAP) is a fluorescent-protein-based detection technique used to quantify protein movement rates within the cell. This method exposes a small portion of the cell to an intense laser beam. The laser beam causes permanent photobleaching of the fluorophore-tagged proteins in the exposed region. As the bleached...
Fluorescent recovery after photobleaching (FRAP) is a fluorescent-protein-based detection technique used to quantify protein movement rates within the cell. This method exposes a small portion of the cell to an intense laser beam. The laser beam causes permanent photobleaching of the fluorophore-tagged proteins in the exposed region. As the bleached...
2.6K
¹H NMR of Labile Protons: Temporal Resolution
1.7K
Protons bonded to heteroatoms such as nitrogen and oxygen exhibit a range of chemical shift values. This is due to the varying degree of hydrogen bonding between the proton and the heteroatom in other molecules. The extent of hydrogen bonding affects the electron density around the proton, thereby giving different chemical shift values for the protons in the proton NMR spectrum.
The –OH proton in alcohols typically appears in the range of δ 2 to 5 ppm but can vary depending on the specific...
The –OH proton in alcohols typically appears in the range of δ 2 to 5 ppm but can vary depending on the specific...
1.7K
¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)
1.6K
When proton-coupled carbon-13 spectra are simplified by a broadband proton decoupling technique, structural information about the coupled protons is lost. Distortionless enhancement by polarization transfer (DEPT) is a technique that provides information on the number of hydrogens attached to each carbon in a molecule. While the DEPT experiment utilizes complex pulse sequences, the pulse delay and flip angle are specifically manipulated. The resulting signals have different phases depending on...
1.6K
Double Resonance Techniques: Overview
693
Double resonance techniques in Nuclear Magnetic Resonance (NMR) spectroscopy involve the simultaneous application of two different frequencies or radiofrequency pulses to manipulate and observe two distinct nuclear spins. One important application of double resonance is spin decoupling, which selectively suppresses coupling with one type of nucleus while observing the NMR signal from another nucleus, simplifying the spectrum and enhancing resolution.
Spin decoupling is usually achieved by...
Spin decoupling is usually achieved by...
693


