Share Your Science: Calculating High-Accuracy Molecular Energies With GPUs

Janus Juul Eriksen, a Ph.D. fellow at Aarhus University in Denmark, shares how he is using OpenACC to optimize and accelerate the quantum chemistry code LSDalton on the Titan Supercomputer at Oak Ridge National Laboratory.

“OpenACC makes GPU computing approachable for domain scientists,” said Eriksen. “Initial OpenACC implementation required only minor effort, and more importantly, no modifications of our existing CPU implementation.”

A recent case study on the project mentions the research team achieved up to 12x speedups using OpenACC compared to the CPU-only code after modifying fewer than 100 lines of code with one week of programming effort.

For more details on Eriksen’s quantum chemistry research, read his latest paper “Efficient and portable acceleration of quantum chemical many-body methods in mixed floating point precision using OpenACC compiler directives.”

Share your GPU-accelerated science with us at and with the world on #ShareYourScience.

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  • Alyona Piven