DFT calculations of 1H chemical shifts, simulated and experimental NMR spectra for sarcosine

Chemical shifts delta have been calculated for the H-1 attached to carbon atoms of sarcosine. Eight levels of theory within the DFT approach were used, mixing the four functionals B3LYP, PBE, OPBE, PBE0 and the two basis sets 6-311++G** and pcJ2. Boltzmann weighted isomer effects have been evaluated. By comparison of the H-1 NMR spectrum simulated from the calculated d and the experimental one that we acquired at 300 MHz, the B3LYP/6-311++G** calculation was seen to be a good compromise between accuracy and cost. Zero-point vibrational corrections, estimated using a second-order perturbation approach, increase the agreement with experiment. (C) 2010 Elsevier B.V. All rights reserved.