激发状态的潜在能量表面,用于腺因的光物理
1Institut de Química Computacional, Departament de Química, Universitat de Girona, ES-17071 Girona, Spain. lluis.blancafort@udg.es
Journal of the American Chemical Society
|January 5, 2006
概括
计算揭示了9H-氨酸激发状态的三个衰变路径. (1) L (b) 状态表现出快速衰变,而 (n,pi) 状态表现出较慢的衰变,解释了观察到的光物理元件.
科学领域:
- 摄影化学的使用.
- 量子化学 是一个量子化学.
- 分子光谱学 分子光谱学
背景情况:
- 了解像9H-氨酸这样的DNA基的兴奋状态动态对于光生物学和光化学至关重要.
- 之前的研究已经提出了复杂的衰变途径,但缺乏详细的理论见解.
研究的目的:
- 通过计算来研究9H-亚丁因单体激发状态表面上的衰变机制和能量障碍.
- 为了阐明实验观察到的短寿命和长寿命兴奋状态元件的起源.
主要方法:
- 使用CAS-PT2//CASSCF理论水平计算衰变路径和能量障碍.
- 分析了三个基本的光物理路径:直接衰变,中间形成和系统间交叉.
主要成果:
- 确定了两个几乎没有障碍的衰变路径,用于 (1) L (b) 状态,导致快速衰变 (约. 0.1 ps) 的时间.
- 标志着 (n,pi) 状态的基态衰变的第三条路径具有~0.1 eV屏障,有助于延长寿命 (≥1 ps).
- 提出了一个三元组 (pi,pi) 状态,通过从单元组 (n,pi) 状态的系统间交叉形成,作为纳秒范围激发状态组件的来源.
结论:
- 计算的衰变路径和相关的能量景观解释了观察到的激发状态高原和 (1) L (b) 和 (n,pi) 状态的井面特征.
- (1) L (b) 状态的直接衰变可能解释了衰变组件的实验波长依赖幅度.
- 这项研究为解释9H-氨酸复杂光物理学的理论框架.
相关概念视频
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The bonds of adenosine triphosphate (ATP) can be broken through the addition of water, releasing one or two phosphate groups in an exergonic process called hydrolysis. This reaction liberates the energy in the bonds for use in the cell—for instance, to synthesize proteins from amino acids.
If one phosphate group is removed, a molecule of ADP—adenosine diphosphate—remains, along with inorganic phosphate. ADP can be further hydrolyzed to AMP—adenosine monophosphate—by the removal of a second...
If one phosphate group is removed, a molecule of ADP—adenosine diphosphate—remains, along with inorganic phosphate. ADP can be further hydrolyzed to AMP—adenosine monophosphate—by the removal of a second...
01:08Hydrolysis of ATP
The bonds of adenosine triphosphate (ATP) can be broken through the addition of water, releasing one or two phosphate groups in an exergonic process called hydrolysis. This reaction liberates the energy in the bonds for use in the cell—for instance, to synthesize proteins from amino acids.
If one phosphate group is removed, a molecule of ADP—adenosine diphosphate—remains, along with inorganic phosphate. ADP can be further hydrolyzed to AMP—adenosine monophosphate—by the removal of a second...
If one phosphate group is removed, a molecule of ADP—adenosine diphosphate—remains, along with inorganic phosphate. ADP can be further hydrolyzed to AMP—adenosine monophosphate—by the removal of a second...
01:18ATP Synthase: Structure
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01:31ATP Energy Storage and Release
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One example of energy coupling using ATP involves a...
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