CLB18: A New Structural Database with Unusual Carbon–Carbon Long Bonds

16 November 2020, Version 1
This content is a preprint and has not undergone peer review at the time of posting.


In this Letter, we introduce a new database called carbon long bond 18 (CLB18), composed of 18 structures with one long C–C bond. We use this new database to evaluate the performance of several low-cost methods commonly used for geometry optimization of medium and large molecules. We found that the long bonds in CLB18 are electronically different from those found in barrier heights databases. We also report the unexpected correlation between the results of CLB18 and those of the energetics of spin states in transition-metal complexes. Given this unique property, CLB18 can be a useful tool for assessing existing electronic structure calculation methods and developing new ones.


Computational Chemistry
Density Functional Calculations
density functional theory
Geometry Optimization

Supplementary materials

CLB18 SuppInfo


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