nistwebbook

name	nistwebbook
description	Look up chemical data from NIST Chemistry WebBook (thermochemistry, spectra, properties)
metadata	null

NIST Chemistry WebBook

Query the NIST Chemistry WebBook for thermochemical, spectral, and property data. Data are from NIST Standard Reference Database 69.

Overview

• Search by compound name, chemical formula, CAS Registry Number, or InChI/InChIKey
• Retrieve thermochemistry, IR/MS/UV-Vis spectra, gas chromatography, and basic properties
• Optional: install nistchempy for full programmatic search; otherwise script prints WebBook URLs for manual lookup

Usage

Search by name (requires nistchempy)

python3 {baseDir}/scripts/nistwebbook_search.py --query "water"

Look up by CAS number (requires nistchempy)

python3 {baseDir}/scripts/nistwebbook_search.py --cas "7732-18-5"

Get WebBook URL only (no nistchempy needed)

python3 {baseDir}/scripts/nistwebbook_search.py --query "methane" --url-only

Limit results

python3 {baseDir}/scripts/nistwebbook_search.py --query "ethanol" --max-results 3

Parameters

Parameter	Description	Default
--query	Compound name or formula	-
--cas	CAS Registry Number (e.g. 7732-18-5)	-
--max-results	Max compounds to return	5
--url-only	Only print NIST WebBook search URL (no nistchempy)	false
--format	summary or json	summary

Output

• Summary: Name, formula, CAS RN, molecular weight; links to thermochemistry/spectra on WebBook
• JSON: Structured data when using nistchempy
• Without nistchempy: script prints the WebBook search URL so users can open it in a browser

Notes

• Install for full search: pip install nistchempy (also needs requests, bs4, pandas)
• NIST does not provide an official API; nistchempy is an unofficial wrapper
• Reference: NIST Chemistry WebBook