Comment on "Quantum interference effects in biphenyl dithiol for gas detection" by J. Prasongkit and A. R. Rocha, RSC Adv. , 2016, 64 , 59299-59304.

The paper [Prasongkit et al. , RSC Adv. , 2016, 64 , 59299] by Prasongkit and Rocha calculates the binding energy of gas molecules attached to 1-8-biphenyl-dithiol (BPDT) molecules. We find from our calculations, that the binding energies calculated for the NO ₂ molecules are too low, most likely due to lacking optimization of the site at which the gas molecule binds to the BPDT. Though not shown explicitly here, the same statement might apply to the other gas molecules used in this paper.
Competing Interests: The group of K. Leifer working in Electron Microscopy and Nano-Engineering at Uppsala University, Sweden, has carried out gas sensor measurements since 2009 starting with measurements on graphene.5 On the background of the gas sensing work on graphene, Leifer proposed in 2011 to build a nanoMoED (nanomolecular electronics) device functionalized with BPDT and try to carry out gas sensing experiments with environmental gases. This idea was nourished by the interdisciplinary centre at Uppsala University, U3MEC (Uppsala University Unimolecular Electronics Centre). After successful initial results, in 2013, we gathered again with the colleagues from theory to discuss possible DFT calculations of the gas sensing effects in uni-molecular devices. At this time, J. Prasongkit was a guest researcher at Uppsala University and our theory colleagues invited her to the meetings.
(This journal is © The Royal Society of Chemistry.)