MoleculeEquivalentQ

As of Version 13.0, MoleculeEquivalentQ has been superseded by MoleculeMatchQ.

MoleculeEquivalentQ[mol1,mol2]

gives True if mol1 and mol2 represent equivalent molecules and gives False otherwise.

Details

  • Two molecules are by default considered equivalent if there is a reordering of atom and bond lists that makes them the same, including any defined stereochemistry.
  • Atoms are considered equal if their atomic number, charge and mass number are the same. Bonds are considered equal if they have the same bond order.
  • For the purpose of equivalence testing, implicit and explicit hydrogen atoms are treated the same.
  • MoleculeEquivalentQ[mol1,mol2,…] gives True if all of the moli are equivalent.

Examples

Basic Examples  (4)

Methane and the ammonium ion have identical connectivity but different atoms, so they are not equivalent:

Even though the underlying graphs are isomorphic, the molecules are not equivalent:

When molecules are the same, apart from the ordering of their atoms and bonds, MoleculeEquivalentQ will return True:

If the stereochemistry is different, then the molecules are not considered equivalent:

Test molecules with isotopic substitutions:

Implicit and explicit hydrogen atoms are treated the same by MoleculeEquivalentQ:

Wolfram Research (2019), MoleculeEquivalentQ, Wolfram Language function, https://reference.wolfram.com/language/ref/MoleculeEquivalentQ.html.

Text

Wolfram Research (2019), MoleculeEquivalentQ, Wolfram Language function, https://reference.wolfram.com/language/ref/MoleculeEquivalentQ.html.

CMS

Wolfram Language. 2019. "MoleculeEquivalentQ." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/MoleculeEquivalentQ.html.

APA

Wolfram Language. (2019). MoleculeEquivalentQ. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/MoleculeEquivalentQ.html

BibTeX

@misc{reference.wolfram_2024_moleculeequivalentq, author="Wolfram Research", title="{MoleculeEquivalentQ}", year="2019", howpublished="\url{https://reference.wolfram.com/language/ref/MoleculeEquivalentQ.html}", note=[Accessed: 21-December-2024 ]}

BibLaTeX

@online{reference.wolfram_2024_moleculeequivalentq, organization={Wolfram Research}, title={MoleculeEquivalentQ}, year={2019}, url={https://reference.wolfram.com/language/ref/MoleculeEquivalentQ.html}, note=[Accessed: 21-December-2024 ]}