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Species Type: Clarification on Atom Syntax #259

Open s9105947 opened 2 years ago

s9105947 commented 2 years ago

In the species type extension: Are temporary (three-letter UuX) to be supported by default?
E.g. "Any one or two-letter abbreviation from the periodic table, defined by..."

I'm not sure if the three-letter symbols where ever part of the official periodic table, though a couple I had included them.

Is the case fixed?
E.g. "The first letter must be in upper case, and the second (should it exist) in lower case." or simply "The element name is case-sensitive."

Also regarding the language:
Is an isotope also an atom? I.e. can isotopes be used to construct ions and molecules?

ax3l commented 2 years ago

Q:

Are temporary (three-letter UuX) to be supported by default?

Current standard:

Element namings follow the abbreviated namings of the periodic table, defined by The International Union of Pure and Applied Chemistry (IUPAC). An example would be Si for silicon.

So I would say, if IUPAC gave out that temporary name, then yes, no problem. Note that temporarily here means usually ~10 years (and is easy to translate once a new name gets assigned).

Is the case fixed? E.g. "The first letter must be in upper case, and the second (should it exist) in lower case." or simply "The element name is case-sensitive."

Sounds good, feel free to add this in the first paragraph via a PR.

Q:

regarding the language: Is an isotope also an atom?

Isotopes are atoms, we just list them explicitly in the section title and 2nd paragraph to make sure people find it.

Q:

I.e. can isotopes be used to construct ions and molecules?

Yes, the 2nd paragraph shows such an example. Current standard:

Specifications of isotopes are denoted by a pound symbol # followed by the isotopic number followed by the chemical symbol, e.g.: #3He for Helium-3.

Note that we intentionally do not encode charged (ion) vs. neutral (atom/isotope) here. See the third paragraph. Current standard:

The charge state is not encoded by the speciesType attribute. Any extension using this standard can define how to specify the charge state.