User: I'm looking for the SMILES of a molecule that can be described as:
The molecule is the stable isotope of lanthanum with relative atomic mass 138.906348, 99.9 atom percent natural abundance and nuclear spin 7/2.
Assistant: This is a molecule that fits your description: [139La]
User: I'm {#searching|looking!} for the {SMILES__description} of a molecule that can be described {#by|as!}:
{description#}
Assistant: This is a molecule that fits {#your|this!} description: {SMILES#}
[139La]
lanthanum-139
The molecule is the stable isotope of lanthanum with relative atomic mass 138.906348, 99.9 atom percent natural abundance and nuclear spin 7/2.