関連する実験動画
Updated: Jan 17, 2026

08:51
Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers
Published on: August 18, 2017
10.9K
表面上のイソマーと非常に類似した分子の正確な差別化のための2段階の機械学習フレームワーク
Zixuan Wei1, Qigang Zhong2, Jinbo Pan1
1Institute of Physics and University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.
Journal of the American Chemical Society
|September 18, 2025
まとめ
ReSTOLOはコンボリューションニューラルネットワーク (CNN) を用いた新しいフレームワークで,スキャニングトンネル顕微鏡 (STM) 画像から表面上の類似分子を正確に識別します. この自動化されたアプローチは,複雑な表面反応の検出精度を向上させます.
科学分野:
- 表面科学
- ナノテクノロジー
- コンピュータ化学
背景:
- 化学反応を理解するために,表面上の有機同位体や類似の分子の正確な検出は不可欠です.
- 現在の方法は,表面上の密接に関連した分子を区別するための効率性,強度,自動化が欠けている.
研究 の 目的:
- 表面に稀に分布する複数の種類の分子を検出し,特定するための自動化された正確なフレームワークを開発する.
- スキャントンネル顕微鏡 (STM) 画像で類似した特徴を持つ分子を区別する課題に取り組む.
主な方法:
- ReSTOLOという2段階のコンボリューションニューラルネットワーク (CNN) フレームワークを実装しました.
- 分子局所化のためにYOLO v5.mと分類のためにResNet-101を使用し,ボックス標準化で接続しました.
- シングル分子の拡張STM画像データベースでモデルを訓練した.
主要な成果:
- 従来の方法と比較して,精度,リコール,精度で約20%の改善を達成しました.
- ほぼ同一のSTMシグネチャーを示す6つの分子で表面反応を分析する際の効果が実証された.
- 類似の構成を持つ分子種を 自動的に特定し区別する 強力な能力を示しました
結論:
- ReSTOLOは,複雑な表面反応における精密な分子差別化のための効率的で自動化されたソリューションを提供します.
- このフレームワークは,STMチップ操作された表面化学の分野を大幅に前進させる.
- このアプローチは,表面反応機構と分子特性の詳細な分析を容易にする.
関連する概念動画
Stereoisomers
17.5K
On the basis of mirror symmetry, stereoisomers of an organic molecule can be further classified into diastereomers and enantiomers. Diastereomers are stereoisomers that are not mirror images of each other. Substituted alkenes, such as the cis and trans isomers of 2-butene, are diastereomers, as these molecules exhibit different spatial orientations of their constituent atoms, are not mirror images of each other, and do not interconvert. Here, the interconversion is suppressed due to...
17.5K
Isomerism
22.9K
Isomers are molecules with the same molecular formula but different structural arrangements. Isomers can be further classified into constitutional isomers and stereoisomers. Constitutional isomers differ in the connectivity of their constituent atoms. For example, 2-butanol and diethyl ether are constitutional isomers, as they have the same chemical formula, C4H10O, but differ in the connectivity of the carbon and oxygen atoms. Constitutional isomers have different physical and chemical...
22.9K
High-Resolution Mass Spectrometry (HRMS)
2.4K
The resolution of a mass spectrometer depends on the efficiency of separating ions with different ion masses. The mass of an atom is approximated to the sum of the masses of protons and neutrons inside, considering the masses of protons and neutrons as equal. However, the masses of the proton (1.6726 × 10−24 g) and neutron (1.6749 × 10−24 g) are not truly equal. There is a minor error in the expression of atomic masses relative to the simplest atom of hydrogen. For...
2.4K
Molecules with Multiple Chiral Centers
14.8K
Molecules that possess multiple chiral centers can afford a large number of stereoisomers. For instance, while some molecules like 2-butanol have one chiral center, defined as a tetrahedral carbon atom with four different substituents attached, several molecules like butane-2,3-diol have multiple chiral centers. A simple formula to predict the number of stereoisomers possible for a molecule with n chiral centers is 2n. However, there can be a lower number where some of the stereoisomers are...
14.8K
Stereoisomerism of Cyclic Compounds
10.9K
In this lesson, we delve into the role of ring conformation and its stability, which determines the spatial arrangement and, consequently, the molecular symmetry and stereoisomerism of cyclic compounds. 1,2-Dimethylcyclohexane is used as a case study to evaluate the possible number of stereoisomers. Here, given the multiple (n = 2) chiral centers, there are 2n = 4 possible configurations that lack a plane of symmetry, as the ring skeleton exists in a non-planar chair conformation. In addition,...
10.9K
Racemic Mixtures and the Resolution of Enantiomers
21.4K
A racemic mixture, or racemate, is an equimolar mixture of enantiomers of a molecule that can be separated using their unique interaction with chiral molecules or media. Racemic mixtures are denoted by the (±)- prefix. This ‘optical rotation descriptor’ applies to the whole solution of a racemic mixture rather than a specific stereoisomer. Enantiomers typically have the same physical and chemical properties. Hence, they are not easily separable. However, enantiomers can exhibit...
21.4K

