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 | ||
|---|---|---|---|---|---|
| 4-BENZOYLOXYCYCLOHEXANONE | C13H14O3 | Mass Spec | Chemical | MassBank | |
| 4-BENZYL-1,3,5-TRIMETHYLPYRAZOLE | C13H16N2 | Mass Spec | Chemical | MassBank | |
| 4-BENZYL-3,4,5-TRIMETHYLPYRAZOLE | C13H16N2 | Mass Spec | Chemical | MassBank | |
| 4-BENZYL-3,5-DIMETHYLISOXAZOLE | C12H13NO | Mass Spec | Chemical | MassBank | |
| 4-BENZYL-3,5-DIMETHYLPYRAZOLE | C12H14N2 | Mass Spec | Chemical | MassBank | |
| 4-BENZYLAMINO-2(5H)-FURANONE | C11H11NO2 | Mass Spec | Chemical | MassBank | |
| 4-BENZYLOXY-2,3,5-TRIMETHYLTHIOPHENOL | C16H18OS | Mass Spec | Chemical | MassBank | |
| 4-BENZYLOXY-2-METHYL-1,3-BUTADIENE | C12H14O | Mass Spec | Chemical | MassBank | |
| 4-BENZYLOXY-2-METHYL-1-BUTEN-3-ONE | C12H14O2 | Mass Spec | Chemical | MassBank | |
| 4-BENZYLOXY-2-METHYL-2-BUTEN-1-OL | C12H16O2 | Mass Spec | Chemical | MassBank | |
| 4-BENZYLOXY-2-METHYL-2-BUTENAL | C12H14O2 | Mass Spec | Chemical | MassBank | |
| 4-BENZYLOXY-3-HYDROXY-2-METHYL-1-BUTENE | C12H16O2 | Mass Spec | Chemical | MassBank | |
| 4-BENZYLOXYBENZALDEHYDE | C14H12O2 | Mass Spec | Chemical | MassBank | |
| 4-BENZYLPYRIDINE | C12H11N | Mass Spec | Chemical | MassBank | |
| 4-BIPHENYLYL 3-CHLOROPHENYL KETONE | C19H13ClO | Mass Spec | Chemical | MassBank | |
| 4-BIPHENYLYL METHYL KETONE | C14H12O | Mass Spec | Chemical | MassBank | |
| 4-BIPHENYLYLMETHYL BENZOATE | C20H16O2 | Mass Spec | Chemical | MassBank | |
| 4-BROMO-1,2-EPOXY-2-METHYLBUTANE | C5H9BrO | Mass Spec | Chemical | MassBank | |
| 4-BROMO-1-BUTENE | C4H7Br | Mass Spec | Chemical | MassBank | |
| 4-BROMO-2,6-DIMETHYLANILINE | C8H10BrN | Mass Spec | Chemical | MassBank | |
| 4-BROMO-2,6-DIMETHYLPHENOL | C8H9BrO | Mass Spec | Chemical | MassBank | |
| 4-BROMO-2-(4-FLUOROPHENYL)PYRIMIDINE | C10H6BrFN2 | Mass Spec | Chemical | MassBank | |
| 4-BROMO-2-METHYL-1-BUTENE | C5H9Br | Mass Spec | Chemical | MassBank | |
| 4-BROMO-2-METHYLBUTENAL | C5H9BrO | Mass Spec | Chemical | MassBank | |
| 4-BROMO-2-NITRO-(PHENYLMETHYLENE)AZANOL | C7H5BrN2O3 | Mass Spec | Chemical | MassBank | |
| 4-BROMO-3,5-DIMETHYLISOXAZOLE | C5H6BrNO | Mass Spec | Chemical | MassBank | |
| 4-BROMO-3,5-DIPHENYLISOXAZOLE | C15H10BrNO | Mass Spec | Chemical | MassBank | |
| 4-BROMO-6-(4-FLUOROPHENYL)PYRIMIDINE | C10H6BrFN2 | Mass Spec | Chemical | MassBank | |
| 4-BROMO-6-HYDROXY-7-METHOXY-2-PHENYL-1,3-DIAZAAZULENE | C15H11BrN2O2 | Mass Spec | Chemical | MassBank | |
| 4-BROMO-N,N-BIS(TRIMETHYLSILYL)ANILINE | C12H22BrNSi2 | Mass Spec | Chemical | MassBank | |
| 4-BROMOANILINE | C6H6BrN | Mass Spec | Chemical | MassBank | |
| 4-BROMOBENZOIC ACID | C7H5BrO2 | Mass Spec | Chemical | MassBank | |
| 4-BROMOBENZONITRILE | C7H4BrN | Mass Spec | Chemical | MassBank | |
| 4-BROMOBENZOYLMETHYL (12Z,15Z)-9,10-EPOXYOCTADECADIENOATE | C26H35BrO4 | Mass Spec | Chemical | MassBank | |
| 4-BROMOBENZOYLMETHYL (9Z,12Z)-15,16-EPOXYOCTADECADIENOATE | C26H35BrO4 | Mass Spec | Chemical | MassBank | |
| 4-BROMOBENZOYLMETHYL (9Z,15Z)-12,13-EPOXYOCTADECADIENOATE | C26H35BrO4 | Mass Spec | Chemical | MassBank | |
| 4-BROMOBENZOYLMETHYL(12Z)-9,10-EPOXYOCTAD | C26H37BrO4 | Mass Spec | Chemical | MassBank | |
| 4-BROMOBENZYL ALCOHOL | C7H7BrO | Mass Spec | Chemical | MassBank | |
| 4-BROMOBENZYL-2-TETRAHYDROPYRANYL ETHER | C12H15BrO2 | Mass Spec | Chemical | MassBank | |
| 4-BROMOBUTYROPHENONE | C10H11BrO | Mass Spec | Chemical | MassBank | |
| 4-BROMOPHENOL | C6H5BrO | Mass Spec | Chemical | MassBank | |
| 4-BROMOPHENYL METHYL KETONE | C8H7BrO | Mass Spec | Chemical | MassBank | |
| 4-BROMOPHENYL PHENYL ETHER | C12H9BrO | Mass Spec | Chemical | MassBank | |
| 4-BROMOPHENYLACETIC ACID | C8H7BrO2 | Mass Spec | Chemical | MassBank | |
| 4-BROMOPHENYLBORIC ACID | C6H6BBrO2 | Mass Spec | Chemical | MassBank | |
| 4-BROMOPROPIOPHENONE | C9H9BrO | Mass Spec | Chemical | MassBank | |
| 4-BUTANOLIDE | C4H6O2 | Mass Spec | Chemical | MassBank | |
| 4-BUTOXYBENZALDEHYDE | C11H14O2 | Mass Spec | Chemical | MassBank | |
| 4-BUTOXYBENZOIC ACID METHYL ESTER | C12H16O3 | Mass Spec | Chemical | MassBank | |
| 4-BUTOXYBENZOIC ACID TRIMETHYLSILYL ESTER | C14H22O3Si | Mass Spec | Chemical | MassBank |