Fingerprint region

Infrared (IR) Spectroscopy · Chemistry

Molecule viewer

Interactive 3D

Ball-and-stick models with true bond angles — switch molecule to compare shapes.

Controls

Drag the sliders or type a value — the simulation updates live.

Molecule

Study notes

Two bottles both show C=O at 1715 cm⁻¹. How does IR tell them apart? Step 1: Functional-group region (>1500) identical — both have carbonyl. Step 2: Compare fingerprint region (<1500) — bending patterns differ. Step 3: Match each against library spectra. Step 4: Fingerprints decide — same pattern = same molecule!