NIST PAH Database

Note: this website was formerly called the NIST Polycyclic Aromatic Hydrocarbon Structure Index to correspond with SP922. The new, shorter name is more convenient for web presentation, especially on mobile and touchscreen devices, one major focus of the 2015 database update.

All data in this database is derived from quantum chemistry computations. Other data that is more accurate, particularly from experimental sources, may be available elsewhere.

This web site incorporates all of the structures found in SP922 plus a number of additional related structures. More structures may be added over time based on user needs and feedback as well as our own interests. In addition to the 2d structures which are included in SP922, 3d structures have been produced using density functional theory (DFT) optimizations. The 3d structures may be freely rotated using the JSMol viewer incorporated into this web page. Also, the 2d and 3d structures may be downloaded for further use.

A great deal of additional information is being made available in the 2015 release, much of it for the first time. Links to PubChem and ChemSpider are included. IR and UV/Vis spectra are plotted, and nucleus independent chemical shift (NICS) values can be displayed at selected points on a 3d model. A number of chemical properties are taken from the output of the quantum chemistry calculations. Other property data from the ZENO (transport properties) and the EPA EPI Suite codes are included.