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Sicklist Database



Russell D. Johnson III


This is a database of problems that arise from using a particular ab initio computational method with a particular molecule. It is intended to serve as a guide to prevent people from wasting resources struggling with known problems and to offer solutions to work around molecules with computational problems.The types of problems in the Sicklist database include wrong geometries, unreasonable vibrational frequencies, and bad energetics. We are not interested in code dependent problems. Species can be added to the database by anyone over the web. Comments on species present in the database can be added using the full listing page.The database is accessible at:
CCCBDB Computational Chemistry Comparison and Benchmark Database Sicklist


ab initio, computational chemistry, computational problems, database, thermochemistry


Johnson, R. (1999), Sicklist Database, CCCBDB Computational Chemistry Comparison and Benchmark Database Sicklist, [online], (Accessed April 18, 2024)
Created October 1, 1999, Updated February 19, 2017