从X射线发射光谱中提取结构描述符和信息:水性硫酸
E A Eronen1, A Vladyka1, Ch J Sahle2
1Department of Physics and Astronomy, University of Turku, FI-20014 Turun yliopisto, Finland. eemeli.a.eronen@utu.fi.
Physical chemistry chemical physics : PCCP
|August 20, 2024
概括
机器学习增强了液体的X射线光谱分析. 特定的结构描述符,如局部多体张量表示,擅长预测水性硫酸的光谱,揭示度和质子化状态.
科学领域:
- 物理化学 物理化学
- 计算化学的计算化学
- 频谱学是一种光谱学.
背景情况:
- 机器学习为分析复杂的光谱数据提供了新的方法.
- 了解当地的原子环境对于解释液体的X射线光谱学至关重要.
- 已经开发了各种结构描述符家族来代表机器学习模型的这种环境.
研究的目的:
- 为了对六个不同的结构描述器家族的性能进行基准测试,用于对X射线发射光谱的机器学习分析.
- 评估这些描述符在捕获与光谱特征相关的结构信息方面的有效性.
- 为了确定最能预测水性硫酸的X射线光谱的描述符.
主要方法:
- 通过计算生成了24200个硫KβX射线辐射光谱的数据集,用于不同度的水性硫酸.
- 一个前神经网络被训练来预测描述向量的光谱.
- 基于模拟器的组件分析被用于识别光谱相关的结构特征.
主要成果:
- 局部多体张量表示,原子位置的平滑重叠和以原子为中心的对称函数在预测光谱方面表现出卓越的性能.
- 在组件分析过程中观察到类似的描述器性能等级.
- 发现光谱特征主要取决于系统度,在包括次要的结构自由度后可以辨别出质子状态.
结论:
- 特定的结构描述符显著提高了液体X射线光谱的机器学习模型的准确性.
- 机器学习,以有效的描述符为指导,可以成功地将光谱数据与关键的化学和物理特性 (如度和质子化状态) 相对应.
- 这种方法提供了一种强大的工具,可以通过X射线光谱学更深入地了解液相化学系统.
相关概念视频
01:26Spectroscopy of Carboxylic Acid Derivatives
2.2K
Infrared spectroscopy is primarily used to determine the types of bonds and functional groups. In carboxylic acid derivatives, a typical carbonyl bond absorption is observed around 1650–1850 cm−1. For esters, the absorption is recorded at around 1740 cm−1, while acid halides show the absorption at about 1800 cm−1. Another acid derivative, the acid anhydrides, exhibit two carbonyl absorption around 1760 cm−1 and 1820 cm−1, arising from the symmetrical and...
2.2K
01:28IR and UV–Vis Spectroscopy of Carboxylic Acids
3.9K
In IR spectroscopy of carboxylic acids, the C=O bond shows a characteristic band between 1710 and 1760 cm⁻¹, and the O–H bond exhibits a broad band between 2500 and 3300 cm⁻¹.
However, the stretching absorptions for the C=O bond vary depending on the structure of carboxylic acids. The C=O bond of the free carboxylic acids shows a higher stretching frequency, 1760 cm−1, while H-bonded carboxylic acids (dimers) exhibit stretching absorptions at a lower frequency,...
However, the stretching absorptions for the C=O bond vary depending on the structure of carboxylic acids. The C=O bond of the free carboxylic acids shows a higher stretching frequency, 1760 cm−1, while H-bonded carboxylic acids (dimers) exhibit stretching absorptions at a lower frequency,...
3.9K
02:17Structure and Nomenclature of Thiols and Sulfides
4.6K
Thiols and sulfides are sulfur analogs of alcohols and ethers, respectively, where the sulfur atom takes the place of the oxygen atom. Thus, thiols are generally represented as RSH, where R is an alkyl substituent and —SH is the functional group. On the other hand, in sulfides, the central sulfur atom is bonded to two hydrocarbon groups on either side. Depending upon the type of group, sulfides can be either symmetrical or asymmetrical. Both thiols and sulfides display a bent geometry,...
4.6K
01:17Precipitation and Co-precipitation
1.7K
Precipitation and coprecipitation methods can be used to separate a mixture of ions in a solution. In qualitative inorganic analysis, ions that form sparingly soluble precipitates with the same reagent are separated based on the differences in solubility products. For example, consider the separation of Cu(II) and Fe(II) ions by precipitation as insoluble sulfides. First, copper(II) sulfide is precipitated by the addition of acidic H2S, where the dissociation of H2S is suppressed. Adding H2S...
1.7K
01:22Electrophilic Aromatic Substitution: Sulfonation of Benzene
6.0K
Sulfonation of benzene is a reaction wherein benzene is treated with fuming sulfuric acid at room temperature to produce benzenesulfonic acid. Fuming sulfuric acid is a mixture of sulfur trioxide and concentrated sulfuric acid.
6.0K
01:20Atomic Emission Spectroscopy: Overview
1.7K
Atomic emission spectroscopy (AES) is an analytical technique used to determine the elemental composition of a sample by analyzing the light emitted from excited atoms. In AES, atoms in a sample are excited to higher energy levels by thermal energy from high-temperature sources, such as plasma, arcs, or sparks. When these excited atoms return to lower energy states, they emit light at specific wavelengths characteristic of each element. The resulting atomic emission spectrum, which consists of...
1.7K