Browse reference spectra from the USGS Spectral Library Version 7 and other curated sources. Each spectrum includes interactive plots, metadata, and downloadable data.
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| Formula | Modality | Category | Source | ||
|---|---|---|---|---|---|
| UO2F2 | UO2F2 | Raman | Inorganic | CRD Oulu | |
| URACIL | C4H4N2O2 | Mass Spec | Chemical | MassBank | |
| URAMIL | C4H5N3O3 | Mass Spec | Chemical | MassBank | |
| UREA | CH4N2O | Mass Spec | Chemical | MassBank | |
| URETHAN | C3H7NO2 | Mass Spec | Chemical | MassBank | |
| URETHANE | C3H7NO2 | Mass Spec | Chemical | MassBank | |
| URIDINE5DIPHOSPHATE | C9H14N2O12P2 | Mass Spec | Chemical | MassBank | |
| URIDINEDIPHOSPHATENACETYLGALACTOSAMINE | C17H27N3O17P2 | Mass Spec | Chemical | MassBank | |
| URIDINEDIPHOSPHATENACETYLGLUCOSAMINE | C17H27N3O17P2 | Mass Spec | Chemical | MassBank | |
| URIDINEMONOPHOSPHATE | C9H13N2O9P | Mass Spec | Chemical | MassBank | |
| UROCANIC ACID | C6H6N2O2 | Mass Spec | Chemical | MassBank | |
| UV-1130 | C20H23N3O3 | Mass Spec | Natural product | MassBank | |
| UV-1577 | C27H27N3O2 | Mass Spec | Natural product | MassBank | |
| UV-234 | C30H29N3O | Mass Spec | Natural product | MassBank | |
| UV-320 | C20H25N3O | Mass Spec | Natural product | MassBank | |
| UV-326 | C17H18ClN3O | Mass Spec | Natural product | MassBank | |
| UV-327 | C20H24ClN3O | Mass Spec | Natural product | MassBank | |
| UV-328 | C22H29N3O | Mass Spec | Natural product | MassBank | |
| UV-329 | C20H25N3O | Mass Spec | Natural product | MassBank | |
| UV-384 | C27H37N3O3 | Mass Spec | Natural product | MassBank | |
| UV-9 | C16H15N3O | Mass Spec | Natural product | MassBank | |
| UV-PS | C16H17N3O | Mass Spec | Environmental | MassBank | |
| UV120 | C29H42O3 | Mass Spec | Environmental | MassBank | |
| UV320 | C20H25N3O | Mass Spec | Environmental | MassBank | |
| UV9 | C16H15N3O | Mass Spec | Environmental | MassBank | |
| Ubiquinone 30 | C39H58O4 | Mass Spec | Lipid | MassBank | |
| Ultramarine | — | NIR | Man-made | USGS | |
| Umbelliferone | C9H6O3 | Mass Spec | Natural product | MassBank | |
| Undecanedioic acid | C11H20O4 | Mass Spec | Environmental | MassBank | |
| Undecanoate | C11H22O2 | Mass Spec | Chemical | MassBank | |
| Undecanoic acid | C11H22O2 | Mass Spec | Natural product | MassBank | |
| Uniconazole | C15H18ClN3O | Mass Spec | Environmental | MassBank | |
| Uracil SA-U0750 | — | NIR | Organic | USGS | |
| Uracil SA-U0750 75K | — | NIR | Organic | USGS | |
| Uracil SA-U0750 85K | — | NIR | Organic | USGS | |
| Urapidil | C20H29N5O3 | Mass Spec | Chemical | MassBank | |
| Uric acid | C5H4N4O3 | Mass Spec | Chemical | MassBank | |
| Uridine | C9H12N2O6 | Mass Spec | Chemical | MassBank | |
| Uridine 5'-diphosphate | C9H14N2O12P2 | Mass Spec | Metabolite | MassBank | |
| Uridine 5'-diphospho-D-glucose | C15H24N2O17P2 | Mass Spec | Metabolite | MassBank | |
| Uridine 5'-diphospho-N-acetylgalactosamine | C17H27N3O17P2 | Mass Spec | Metabolite | MassBank | |
| Uridine 5'-diphospho-N-acetylglucosamine | C17H27N3O17P2 | Mass Spec | Natural product | MassBank | |
| Uridine 5'-diphosphoglucuronic acid | C15H22N2O18P2 | Mass Spec | Metabolite | MassBank | |
| Uridine 5'-monophosphate | C9H13N2O9P | Mass Spec | Metabolite | MassBank | |
| Urobilinogen | C33H44N4O6 | Mass Spec | Natural product | MassBank | |
| Urocanate | C6H6N2O2 | Mass Spec | Chemical | MassBank | |
| Ursodeoxycholic acid | C24H40O4 | Mass Spec | Chemical | MassBank | |
| Ursolic acid | C30H48O3 | Mass Spec | Natural product | MassBank | |
| Uvinul-LR | C17H26N2O4 | Mass Spec | Environmental | MassBank | |
| V2Se8Rb4Ag2 | V2Se8Rb4Ag2 | Raman | Inorganic | CRD Oulu |