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Accessing the molecular PAH data

The molecular PAH data is accessed through their associated unique identifier (UID). However, a search-interface is available that allows retrieval of these UIDs through simplified queries. The syntax is the same as used on the NASA Ames PAH IR Spectroscopic Database website.

uids = pahdb->Search("c<=20 neutral n=2 neutral")

The molecular PAH data contained in the database XML-files consists of four main parts:

1. Molecular properties, .e.g, molecular weight, zero point energy, total energy, etc.
2. Fundamental vibrational transitions
3. Molecular geometric data
4. Raw laboratory spectra for a subset of molecules in the experimental database

pahdb = OBJ_NEW('AmesPAHdbIDLSuite')

uids = pahdb->Search("c<=20 neutral n=2 neutral")

pahs = pahdb->getSpeciesByUID(uids)

transitions = pahdb->getTransitionsByUID(uids)

geometries = pahdb->getGeometryByUID(uids)

laboratory = pahdb->getLaboratoryByUID(uids)

... work ...

OBJ_DESTROY,[laboratory, $
             geometries, $
             transitions, $
             pahs, $
             pahdb]

Alternatively, one can access these data components through the 'AmesPAHdbIDLSuite_Species'-object.

pahdb = OBJ_NEW('AmesPAHdbIDLSuite')

pahs = pahdb->getSpeciesByUID( $
       pahdb->Search("c<=20 neutral n=2 neutral"))

transitions = pahs->transitions()

geometries = pahs->geometry()

laboratory = pahs->laboratory()

... work ...

OBJ_DESTROY,[laboratory, $
             geometries, $
             transitions, $
             pahs, $
             pahdb]