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Special Publication 922 Polycyclic Aromatic Hydrocarbon Structure Index

NIST Special Publication (SP) 922 is an aid in the identification of the chemical structures of polycyclic aromatic hydrocarbons (PAHs). The Structure Index consists of two parts: (1) a cross index of named PAHs listed in alphabetical order and (2) chemical structures including ring numbering, name(s), Chemical Abstract Service Service (CAS) Registry numbers, chemical formulas, molecular weights, and length-to-breadth ratios (L/B) and shape descriptors of PAHs listed in order of increasing molecular weight. SP 922 is now available as a single file in pdf format (24,793 KB) by clicking here.

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This document was revised in June 2011 to correct known errors. Comments and corrections can be sent to

Created August 31, 2011, Updated September 21, 2016