The most computationally intensive part of the SOS-MP2 algorithm for the calculation of the correlation energy [1], as executed in Q-Chem, is implemented for use in a graphical processing unit (GPU). Our approach adds new routines to the library initially developed by Aspuru-Guzik and co-workers [2, aiming at maximization of bandwidth and performance, by taking advantage of the asynchronous CPU-GPU communication capability of modern GPUs. These changes permit an almost six-fold acceleration in the correlation energy calculation of linear alkanes. This was achieved employing a NVIDIA Tesla K40C (Kepler) GPU and the Compute Unified Device Architecture (CUDA).