### Molecule description

A typical example of a <Molecule> is (truncated for clarity):

      <Molecule speciesID="XCDMS-132">

        <MolecularChemicalSpecies>
          <OrdinaryStructuralFormula>
            <Value>C-13-O-18</Value>
          </OrdinaryStructuralFormula>
          <StoichiometricFormula>CO</StoichiometricFormula>
          <ChemicalName>
            <Value>Carbon Monoxide</Value>
          </ChemicalName>
          <InChI>1S/CO/c1-2/i1+1,2+2</InChI>
          <InChIKey>UGFAIRIUMAVXCW-RGIGPVFXSA-N</InChIKey>
          <VAMDCSpeciesID>UGFAIRIUMAVXCW-RGIGPVFXSA-N</VAMDCSpeciesID>
          <PartitionFunction>
            <T units="K">
              <DataList>1.072 1.148 (truncated) 1000.0</DataList>
            </T>
            <Q>
              <DataList>2.05524705685 2.07536036351 (truncated) 798.466964704</DataList>
            </Q>
          </PartitionFunction>
        </MolecularChemicalSpecies>

        <MolecularState stateID="SCDMS-9240238">
          <MolecularStateCharacterisation>
            <StateEnergy methodRef="MCDMS-6647" energyOrigin="SCDMS-9240238-origin-132">
              <Value units="1/cm">0.0</Value>
            </StateEnergy>
            <TotalStatisticalWeight>2</TotalStatisticalWeight>
            <NuclearStatisticalWeight>2</NuclearStatisticalWeight>
          </MolecularStateCharacterisation>
          <Case>
            <dcs:QNs>
              <dcs:ElecStateLabel>X</dcs:ElecStateLabel>
              <dcs:v>0</dcs:v>
              <dcs:J>0</dcs:J>
              <dcs:F nuclearSpinRef="C-13">0.5</dcs:F>
            </dcs:QNs>
          </Case>
        </MolecularState>

        <MolecularState stateID="SCDMS-9240239">
          <MolecularStateCharacterisation>
            <StateEnergy methodRef="MCDMS-6647" energyOrigin="SCDMS-9240238-origin-132">
              <Value units="1/cm">3.492795</Value>
            </StateEnergy>
            <TotalStatisticalWeight>2</TotalStatisticalWeight>
            <NuclearStatisticalWeight>1</NuclearStatisticalWeight>
          </MolecularStateCharacterisation>
          <Case>
            <dcs:QNs>
              <dcs:ElecStateLabel>X</dcs:ElecStateLabel>
              <dcs:v>0</dcs:v>
              <dcs:J>1</dcs:J>
              <dcs:F nuclearSpinRef="C-13">0.5</dcs:F>
            </dcs:QNs>
          </Case>
        </MolecularState>

      </Molecule>

LINEDB uses the OrdinaryStructuralFormula as the species name, but its InChIKey is used for database queries. The partition function is taken from the PartitionFunction block. It can provide any number of temperatures, it can also be absent. Each energy level of the molecule (energy, quantum numbers, statistical weight) is described in a separated <MolecularState> block.