构建含有碳链的系统的潜在能量表面,使用带有渐进扩张方法的辐射角网络
1University Rennes, CNRS, IPR (Institut de Physique de Rennes) - UMR 6251, F-35000 Rennes, France.
The Journal of chemical physics
|September 25, 2024
概括
我们开发了一种新方法,带有逐渐扩展的辐射角网络 (RANGE),以准确地建模分子相互作用. 这种方法可以计算碳链分子的碰撞诱导的分子激发,如和的聚氨酸.
科学领域:
- 化学物理 化学物理
- 计算化学计算化学
- 分子光谱学 分子光谱学
背景情况:
- 准确的潜在能量表面对于理解碰撞过程中的分子激发至关重要.
- 计算这些表面的碳链分子,如cyanopolyynes,一直是一个重大挑战.
- 这种困难限制了有关的重要碰撞系统的速率系数的可用性.
研究的目的:
- 引入一种新的计算方法,即逐渐扩展的辐射角网络 (RANGE),用于构建分析潜能表面.
- 将RANGE方法应用于聚 - 复合物 (HC3N-He,HC5N-He,HC7N-He).
- 研究这些碰撞系统中支配状态变化的倾向规则.
主要方法:
- 开发了带有逐渐扩展的辐射角网络 (RANGE) 方法,将初始潜力构造与分析形式确定相结合.
- 使用HC3N-He系统作为基准来验证RANGE方法的可靠性.
- 应用了RANGE方法来推导HC5N-He和HC7N-He的分析潜力.
主要成果:
- 通过RANGE方法成功地构建了HC3N-He,HC5N-He和HC7N-He的分析潜能表面.
- 分析揭示了潜在的系统趋势:随着碳链长度的增加,局部最小数和碳原子之间的相关性,以及离合极限附近的一致的浅最小值.
- 量子力学计算表明,HC3N,HC5N和HC7N在He的碰撞激发中对Δj = 2过渡的倾向.
结论:
- RANGE方法提供了一种可靠和高效的方法,用于为复杂的分子系统生成精确的分析潜能表面.
- 这项研究确定了聚烯-复合物的相互作用潜力的关键趋势.
- 确定了有利于Δj = 2过渡的一致倾向规则,用于这些分子被的碰撞激发.
更多相关视频
13:56Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
7.6K
07:16Author Spotlight: Development of a Novel Finite Element Analysis Model for Improved Orthognathic Surgical Techniques
Published on: October 20, 2023
1.2K
相关概念视频
01:17Radical Chain-Growth Polymerization: Chain Branching
1.9K
The skeletal structure of polymers synthesized via radical polymerization is always branched. For example, the polymerization of ethylene by radical polymerization results in a low-density grade of polyethylene with a heavily branched skeletal structure. Here, the radical site abstracts hydrogen from the growing chain, and the radical site shifts from the end (a primary carbon center) to anywhere within the growing chain (a secondary carbon center). Consequently, the part of the chain from the...
1.9K
01:10Radical Chain-Growth Polymerization: Overview
2.4K
Chain-growth or addition polymerization is successive addition reactions of monomers with a polymer chain. In radical chain-growth polymerization, the reaction proceeds via a free-radical intermediate. The free radical is formed from radical initiators, which spontaneously generate free radicals by homolytic fission. Organic peroxides (such as dibenzoyl peroxide, as shown in Figure 1) or azo compounds are popular radical initiators. A low concentration ratio of radical initiator to monomer is...
2.4K
01:09Radical Chain-Growth Polymerization: Mechanism
2.5K
The radical chain-growth polymerization mechanism consists of three steps: initiation, propagation, and termination of polymerization. The polymerization initiates when a free radical generated from the radical initiator adds to the unsaturated bond in the monomer. The unpaired electron of the free radical and one π electron in the unsaturated bond creates a σ bond between the free radical and the monomer. As a result, the other π electron in the unsaturated bond converts this...
2.5K
02:06Newman Projections
16.5K
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...
The organic molecules rotate across the single bonds leading to numerous temporary three-dimensional structures of varying energy known as...
16.5K
02:29Conformations of Cycloalkanes
11.6K
Adolf von Baeyer attempted to explain the instabilities of small and large cycloalkane rings using the concept of angle strain — the strain caused by the deviation of bond angles from the ideal 109.5° tetrahedral value for sp3 hybridized carbons. However, while cyclopropane and cyclobutane are strained, as expected from their highly compressed bond angles, cyclopentane is more strained than predicted, and cyclohexane is virtually strain-free. Hence, Baeyer’s theory that...
11.6K
02:11Conformations of Cyclohexane
12.2K
Cyclohexane does not exist in a planar form due to the high angle and torsional strain it would experience in the planar structure. Instead, it adopts non-planar chair and boat conformations.
The chair form is the most stable and derives its name from its resemblance to the “easy chair.” In the chair conformation, two carbon atoms are arranged out-of-plane — one above and one below, minimizing the torsional strain. In the chair form, the bond angle is very close to the ideal...
The chair form is the most stable and derives its name from its resemblance to the “easy chair.” In the chair conformation, two carbon atoms are arranged out-of-plane — one above and one below, minimizing the torsional strain. In the chair form, the bond angle is very close to the ideal...
12.2K