An intriguing twitter post from Imants Zudans tells us: “Apparently 2 companies are selling atomic hydrogen. I wonder what is the packaging and how it is shipped.”
Zudans provides a link to his MolPort site where you can see for yourself that on the entry for atomic hydrogen (the proton, in other words), Apollo Scientific and Sigma Aldrich are both offering this stuff for sale. Sigma offers no price, but Apollo asks visitors to enquire. Very odd, but they’re obviously just covering all bases for customers searching for hydrogen.
But, it wasn’t the fact that atomic hydrogen is being offered for sale that was most curious it was the incredible difference between the SMILES string and the INCHIkey for the hydrogen atom that caught my eye. Those abbreviated forms of chemical formulae notation that both allow three-dimensional or even two-dimensional flat structures to be represented as a one-dimensional text string are incredibly useful, but I’ve never used either for the hydrogen atom. Nevertheless, the difference between the two is rather amusing:
Hydrogen atom in SMILES = [H]
InChI Key = UFHFLCQGNIYNRP-UHFFFAOYAN
Did I say the InChI Key was an abbreviated form at 25 characters and the SMILEs at three, where H by itself would just about do it for most people.