Thursday, June 16, 2016

The end of unun*iums is announced

So that’s it, then. Four new elements, ununtrium, ununpentium, ununseptium and ununoctium [1] are to be officially named nihonium (symbol Nh), moscovium (Mc), tennessine (Ts), and oganesson (Og), respectively [2]. So that for a while the periodic table will be free of ungainly “unun” names. The provisional recommendation is out [3], comments by 8 November 2016. I am going to send mine to IUPAC, but I’d like to share them with my readers first.

Let’s start with naming conventions [4]:

In keeping with tradition, elements are named after:
  1. a mythological concept or character (including an astronomical object),
  2. a mineral, or similar substance,
  3. a place, or geographical region,
  4. a property of the element, or
  5. a scientist.
Unfortunately, it is not required for the names to be aesthetically pleasing.

In absence of minerals (all four elements are artificial) and properties (apart from half-lives, which aren’t that long) to speak about, we are left with three options. Don’t you agree that the option (a) is the most interesting one? However, the discoverers have chosen easy and boring options (c) and (e). Well, I like nihonium, named after Nihon (ニホン), one of the Japanese names for Japan (literally, “the sun’s origin”). I can’t say the same about the rest.

Take moscovium:

It is proposed that the name moscovium and symbol Mc are given to element 115. Moscovium is recommended in recognition of the Moscow region and honoring the ancient Russian land that is home to the Joint Institute for Nuclear Research, where the discovery experiments were conducted using the Dubna Gas-Filled Recoil Separator in combination with the heavy-ion accelerator capabilities of the Flerov Laboratory of Nuclear Reactions, JINR.
I see. Not content with dubnium (element 105), Russian scientists™ insist on honouring Dubna one more time. But Dubna is not Moscow. The town is at least as old as the Russian capital and is situated on the very edge of Moscow Oblast, or Podmoskovye (Подмосковье). Shouldn’t dubnium 2.0 be called podmoskovium then? And why mention Moscow at all? After all, there are four elements named after Ytterby. The variations like dubinium, dubonium, or poddubnium spring to mind. Needless to say, “Mc” will have to go.

Personally, I would prefer the element 115 to be named lemmium in honour of the late Motörhead frontman Lemmy Kilmister. Alas, IUPAC’s set of absurd rules (see above) restricts people after whom the new elements could be named to “scientists”. I’ll come to that in a minute.

Now let’s look at tennessine. The ending -ine, by analogy with English names of other halogens, appears to be natural. However it simply shows that the authors of this proposal (from Tennessee region, I guess) did not think about languages other than English, although they should have, for “the names for new chemical elements in English should allow proper translationcinto other major languages” [3]. For instance, in Latin the halogen names are fluorum, clorum, bromum, iodum and astatum, in Spanish they are flúor, cloro, bromo, yodo and astato, while in German they are simply Fluor, Chlor, Brom, Iod und Astat. So in these languages the element 117 must be named tennessum, teneso and Tenness, respectively.

As for the symbol, I was about to complain that Ts is is a bad choice for an element symbol as Ts is widely used for tosyl group, and why not to use Tn given that TN is also an abbreviation for Tennessee. There was a similar story with copernicium a few years ago (originally proposed symbol Cp was later changed to Cn). It’s not that the authors of the recommendation aren’t aware of potential confusion:

NB: We are aware of the fact that Ts is often used as abbreviation for the tosyl chemical group. However, this was not considered to be a valid objection, given the fact that we also use the symbols Ac and Pr for chemical elements, while chemists also use these as abbreviations for the acyl and the propyl groups. Very common items like AcOH and PrOH are usually not taken for the hydroxides of actinium and praseodymium and a possible confusion with the tosyl group seem extremely low. On the other hand, the abbreviation Tn, that might have been a natural suggestion, is impossible given the earlier (1923) CIAAW-IUPAC acceptance of that symbol for thoron (220Rn), and its regular usage since then, see e.g. Journal of Environmental Radioactivity.
Still, I don’t find this convincing. If we ever get enough of ununseptium, we’ll find that its chemistry is nothing like that of actinium or praseodymium. Think of tosyl chloride, abbreviated TsCl. Now think of its tennessine analogue, abbreviated TsTs. That’s just silly. It’s a shame we can’t use “Tn” as TN is an abbreviation for the state of Tennessee. What about Tq then, after Tanasqui, the first recorded version of this toponym?

Finally, oganesson. Does it have to end with -on? Yes, most noble gases do (and, in contrast to meaningless -ine, the ending -on is present in other languages). Except helium, that is. Helium was named after Helios, the Greek god of the Sun, and is the only noble gas following the naming principle (a). Several “on” names are of Greek origin, namely νέον “new”, ἀργόν “inactive”, κρυπτόν “hidden” and ξένον “foreign”, whereas radon is a contraction of “radium emanation”. But oganesson... Please! It’s two syllables too many and feels out of place.

And another thing. I don’t know about you, but naming anything after a living person makes me uneasy. Seeing his surname mutilated this way should make Yuri Oganessian uneasy too. Come on, did we ran out of deserving dead scientists whose names, incidentally, can be used for the heaviest known element? For example, we can honour John Dalton, an English polymath best known for development of atomic theory; among other things, he invented his own symbols for chemical elements [5]. Or J. J. Thomson, discoverer of the electron. Or Francis W. Aston, discoverer of many naturally occurring isotopes. Or Arthur Compton, known for Compton scattering. Or C. T. R. Wilson, inventor of the cloud chamber. Or Fritz London, after whom the London dispersion forces are named. Or Ernest Walton, the first person to artificially split the atom.

To summarise: political considerations, inflated egos, and lack of imagination all may be responsible for some of the dismal proposals above. It does not mean we have to swallow them without fight. If you have better suggestions — and I’m sure you do — I urge you to write to IUPAC before 8 November.

  1. IUPAC announces the verification of the discoveries of four new chemical elements: The 7th period of the periodic table of elements is complete. IUPAC Press Release, 30 December 2015.
  2. IUPAC is naming the four new elements nihonium, moscovium, tennessine, and oganesson. IUPAC Press Release, 8 June 2016.
  3. Öhrström, L. and Reedijk, J. (2016) Names and symbols of the elements with atomic numbers 113, 115, 117 and 118. IUPAC Provisional Recommendation.
  4. Koppenol, W.H., Corish, J., García-Martínez, J., Meija, J. and Reedijk, J. (2016) How to name new chemical elements (IUPAC Recommendations 2016). Pure and Applied Chemistry 88, 401—405.
  5. Dalton, J. (1808) A New System of Chemical Philosophy, vol. I.