一个深度学习模型用于分子有机固体中的化学屏蔽,包括 anisotropy
Matthias Kellner1, Jacob B Holmes2, Ruben Rodriguez-Madrid2
1Laboratory of Computational Science and Modeling, Institut des Matériaux, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.
The journal of physical chemistry letters
|August 18, 2025
概括
新的深度学习模型ShiftML3显著提高了预测固体中核磁共振 (NMR) 化学屏蔽的准确性. 这一进步使机器学习预测更接近要求初始计算的准确性.
科学领域:
- 固态核磁共振 (NMR) 光谱学 固态核磁共振 (NMR) 光谱学
- 计算化学是一种计算化学.
- 材料科学是一种材料科学.
背景情况:
- 核磁共振 (NMR) 化学转移对于确定固体材料中的原子和电子结构至关重要.
- 机器学习 (ML) 模型为预测化学屏蔽提供了对初始计算的有效替代方案.
- 当前的ML模型往往缺乏已建立的DFT方法的预测准确性.
研究的目的:
- 介绍ShiftML3,一种深度学习模型,用于增强对NMR化学屏蔽的预测.
- 提高在分子固体中预测同otropic化学屏蔽和完全屏蔽张量器的准确性和效率.
- 为了减少ML模型和DFT计算之间的预测准确度差距.
主要方法:
- 开发了一个名为ShiftML3.3的深度学习模型.
- 在实验基准数据集上的模型的培训和验证.
- 将ShiftML3的预测准确度与DFT参考计算进行比较.
主要成果:
- ShiftML3在预测H,C和N.15的同位素化学屏蔽方面实现了高准确度.
- ShiftML3的根平均平方误差 (RMSEs) 接近DFT计算的误差:0.53 ppm (H),2.4 ppm (C) 和7.2 ppm (N).
- 该模型成功地预测了全屏蔽张量,而不仅仅是同位素值.
结论:
- ShiftML3代表了基于ML的分子固体NMR屏蔽预测的重大进步.
- 该模型的准确性与DFT方法相美,提供了一个更快,更可扩展的替代方案.
- ShiftML3增强了NMR光谱在固态材料结构阐明方面的实用性.
相关概念视频
01:27π Electron Effects on Chemical Shift: Overview
1.1K
An applied magnetic field causes loosely bound π-electrons in organic molecules to circulate, producing a local or induced diamagnetic field over a large spatial volume. As the molecules tumble in solution, the field generated by π-electrons in spherical substituents results in a zero net field. However, the net field generated by π-electrons in non-spherical substituents is not zero. The effect of this induced field depends on the orientation of the molecule with respect to B0,...
1.1K
02:00Molecular Models
40.4K
Physical models representing molecular architectures of chemical compounds play essential roles in understanding chemistry. The use of molecular models makes it easier to visualize the structures and shapes of atoms and molecules.
40.4K
01:17Chemical Shift: Internal References and Solvent Effects
764
In an NMR sample, precise measurement of the absolute absorption frequencies of nuclei is difficult. A standard internal reference compound is added, and the frequency difference between the reference signal and sample signals is measured.
The internal reference compound generally used in NMR spectroscopy is tetramethylsilane (TMS). TMS is preferred because it is chemically inert, soluble in NMR solvents, and easily removable. Also, the highly shielded methyl protons in TMS yield an intense...
The internal reference compound generally used in NMR spectroscopy is tetramethylsilane (TMS). TMS is preferred because it is chemically inert, soluble in NMR solvents, and easily removable. Also, the highly shielded methyl protons in TMS yield an intense...
764
01:27Inductive Effects on Chemical Shift: Overview
1.3K
The protons in unsubstituted alkanes are strongly shielded with chemical shifts below 1.8 ppm. Methine, methylene, and methyl protons appear at approximately 1.7, 1.2 and 0.7 ppm, while the proton signal from methane appears at 0.23 ppm. An electronegative substituent, such as chlorine, withdraws the electron density from the protons, increasing their chemical shift. Progressive substitution of the hydrogens in methane by chlorine shifts the proton signals increasingly downfield, to 3.05 ppm in...
1.3K
02:27Predicting Molecular Geometry
35.9K
VSEPR Theory for Determination of Electron Pair Geometries
35.9K
01:14Diamagnetic Shielding of Nuclei: Local Diamagnetic Current
960
An applied magnetic field causes the electrons present in the molecule to circulate, setting up a local diamagnetic current within the molecule. The local diamagnetic current arising from circulating sigma-bonding electrons induces a magnetic field, Blocal that opposes the applied magnetic field, B0. The effective magnetic field experienced by these nuclei is given by the difference between the applied and local magnetic fields in a phenomenon called local diamagnetic shielding. Essentially,...
960