scholarly journals KINETICS: A computer program to analyze chemical reaction data. Revision 2

1994 ◽  
Author(s):  
R.L. Braun ◽  
A.K. Burnham
Keyword(s):  
Computer Program ◽  
Chemical Reaction ◽  
Reaction Data ◽  
Data Revision

scholarly journals Improving machine learning performance on small chemical reaction data with unsupervised contrastive pretraining

2022 ◽  
Author(s):  
Mingjian Wen ◽  
Samuel M. Blau ◽  
Xiaowei Xie ◽  
Shyam Dwaraknath ◽  
Kristin A. Persson
Keyword(s):  
Machine Learning ◽  
Chemical Reaction ◽  
Chemical Space ◽  
Relevant Information ◽  
Learning Performance ◽  
Reaction Data ◽  
Unlabelled Data ◽  
Graph Neural Networks ◽  
Small Chemical ◽  
Fine Tune

Machine learning (ML) methods have great potential to transform chemical discovery by accelerating the exploration of chemical space and drawing scientific insights from data. However, modern chemical reaction ML models, such as those based on graph neural networks (GNNs), must be trained on a large amount of labelled data in order to avoid overfitting the data and thus possessing low accuracy and transferability. In this work, we propose a strategy to leverage unlabelled data to learn accurate ML models for small labelled chemical reaction data. We focus on an old and prominent problem—classifying reactions into distinct families—and build a GNN model for this task. We first pretrain the model on unlabelled reaction data using unsupervised contrastive learning and then fine-tune it on a small number of labelled reactions. The contrastive pretraining learns by making the representations of two augmented versions of a reaction similar to each other but distinct from other reactions. We propose chemically consistent reaction augmentation methods that protect the reaction center and find they are the key for the model to extract relevant information from unlabelled data to aid the reaction classification task. The transfer learned model outperforms a supervised model trained from scratch by a large margin. Further, it consistently performs better than models based on traditional rule-driven reaction fingerprints, which have long been the default choice for small datasets. In addition to reaction classification, the effectiveness of the strategy is tested on regression datasets; the learned GNN-based reaction fingerprints can also be used to navigate the chemical reaction space, which we demonstrate by querying for similar reactions. The strategy can be readily applied to other predictive reaction problems to uncover the power of unlabelled data for learning better models with a limited supply of labels.

Making chemical reaction data accessible to the non-chemist

1984 ◽  
Vol 33 (1-3) ◽  
pp. 197-203 ◽  
Author(s):  
J. Brandt ◽  
A. von Scholley ◽  
M. Wochner
Keyword(s):  
Chemical Reaction ◽  
Reaction Data

Branch intensities and oscillator strengths for the Herzberg absorption systems in oxygen

1994 ◽  
Vol 72 (11-12) ◽  
pp. 1109-1121 ◽  
Author(s):  
David L. Huestis ◽  
Richard A. Copeland ◽  
Karen Knutsen ◽  
Tom G. Slanger ◽  
Rienk T. Jongma ◽  
...  
Keyword(s):  
Absorption Spectrum ◽  
Computer Program ◽  
Molecular Oxygen ◽  
Chemical Reaction ◽  
Oscillator Strengths ◽  
Experimental Investigations ◽  
Spectral Simulation ◽  
Cavity Ring Down Spectroscopy ◽  
Oxygen Atoms ◽  
Cavity Ring Down

We report two complementary experimental investigations of the absorption spectrum of molecular oxygen between 243 and 258 nm. In the first experiment, excitation of O2 is inferred by detecting oxygen atoms resulting from chemical reaction. In the second experiment, absorption by O2 is observed directly by cavity ring-down spectroscopy. Absorption strengths for the Herzberg I [Formula: see text], Herzberg II [Formula: see text], and Herzberg III [Formula: see text] band systems are modeled with the DIATOM spectral simulation computer program using the best available branch intensity formulas. Absolute oscillator strengths are derived for all three systems and compared with values in the literature.

POLYRATE 6.5: A new version of a computer program for the calculation of chemical reaction rates for polyatomics

1995 ◽  
Vol 88 (2-3) ◽  
pp. 341-343 ◽  
Author(s):  
Rozeanne Steckler ◽  
Wei-Ping Hu ◽  
Yi-Ping Liu ◽  
Gillian C. Lynch ◽  
Bruce C. Garrett ◽  
...  
Keyword(s):  
Computer Program ◽  
Chemical Reaction ◽  
Reaction Rates ◽  
Chemical Reaction Rates

MORATE 6.5: A new version of a computer program for direct dynamics calculations of chemical reaction rate constants

1995 ◽  
Vol 88 (2-3) ◽  
pp. 344-346 ◽  
Author(s):  
Wei-Ping Hu ◽  
Gillian C. Lynch ◽  
Yi-Ping Liu ◽  
Ivan Rossi ◽  
James J.P. Stewart ◽  
...  
Keyword(s):  
Computer Program ◽  
Chemical Reaction ◽  
Rate Constants ◽  
Reaction Rate ◽  
Direct Dynamics ◽  
Reaction Rate Constants ◽  
Chemical Reaction Rate
Sign in / Sign up

Export Citation Format

Share Document