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-BUTOXYPHENOL | C10H14O2 | Mass Spec | Chemical | MassBank | |
| 4-BUTYL-3-OXATRICYCLO(3.3.0.0(4,6))OCTA-2,8-DIONE | C11H14O3 | Mass Spec | Chemical | MassBank | |
| 4-BUTYLANILINE | C10H15N | Mass Spec | Chemical | MassBank | |
| 4-BUTYLBENZOIC ACID TRIMETHYLSILYL ESTER | C14H22O2Si | Mass Spec | Chemical | MassBank | |
| 4-BromoBenzoTriBromide | C7H4Br4 | Mass Spec | Natural product | MassBank | |
| 4-Bromoantipyrine | C11H11BrN2O | Mass Spec | Chemical | MassBank | |
| 4-Butylphenol | C10H14O | Mass Spec | Chemical | MassBank | |
| 4-CARBOXLYBENZALDEHYDE | C8H6O3 | Mass Spec | Chemical | MassBank | |
| 4-CARBOXYL-N-DODECYL-2-PYRROLIDONE | C17H31NO3 | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-1-BUTENE | C4H7Cl | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-1-PHENYLPYRAZOLE | C9H7ClN2 | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-2-(2-HYDROXYPHENYL)-5-PHENYLPYRIMIDINE | C16H11ClN2O | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-2-(3-NITROPHENYL)PYRIMIDINE | C10H6ClN3O2 | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-2-HYDROXYMETHYLPHENOL | C7H7ClO2 | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-3,5-DIMETHYLISOXAZOLE | C5H6ClNO | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-3-BUTEN-2-ONE | C4H5ClO | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-3-HYDROXY-3-METHYLBUTYL ACETATE | C7H13ClO3 | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-3-METHYL-2-BUTENYL ACETATE | C7H11ClO2 | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-3-NITROBENZOIC ACID METHYL ESTER | C8H6ClNO4 | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-3-PHENYLTHIOMETHOXYPHENOL | C13H11ClO2S | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-4'-HYDROXYBIPHENYL | C12H9ClO | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-4-METHYL-2-TRIMETHYLSILOXYPENTENE | C9H19ClOSi | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-4-METHYLPERHYDROPYRAN | C6H11ClO | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-6-(3-FLUOROPHENYL)PYRIMIDINE | C10H6ClFN2 | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-6-(4-FLUOROPHENYL)PYRIMIDINE | C10H6ClFN2 | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-6-METHYL-2-PHENYLPYRIMIDINE | C11H9ClN2 | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-6-PHENYLPYRIMIDINE-1-OXIDE | C10H7ClN2O | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-META-CRESOL | C7H7ClO | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-N,N-BIS(TRIMETHYLSILYL)ANILINE | C12H22ClNSi2 | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-N-(2-(DIETHYLAMINO)ETHYL)BENZAMIDE | C13H19ClN2O | Mass Spec | Chemical | MassBank | |
| 4-CHLORO-N-(4-CHLOROPHENYL)-BENZAMIDE | C13H9Cl2NO | Mass Spec | Chemical | MassBank | |
| 4-CHLOROACETOACETIC ACID ETHYL ESTER | C6H9ClO3 | Mass Spec | Chemical | MassBank | |
| 4-CHLOROACETOPHENONE | C8H7ClO | Mass Spec | Chemical | MassBank | |
| 4-CHLOROBENZOIC ACID | C7H5ClO2 | Mass Spec | Chemical | MassBank | |
| 4-CHLOROBENZOIC ACID METHYL ESTER | C8H7ClO2 | Mass Spec | Chemical | MassBank | |
| 4-CHLOROBENZONITRILE | C7H4ClN | Mass Spec | Chemical | MassBank | |
| 4-CHLOROBENZYL 2-METHYLBENZOATE | C15H13ClO2 | Mass Spec | Chemical | MassBank | |
| 4-CHLOROBENZYLALCOHOL | C7H7ClO | Mass Spec | Chemical | MassBank | |
| 4-CHLOROBIPHENYL | C12H9Cl | Mass Spec | Chemical | MassBank | |
| 4-CHLOROBUTYROPHENONE | C10H11ClO | Mass Spec | Chemical | MassBank | |
| 4-CHLOROMETHYL-3,5-DIMETHYLISOXAZOLE | C6H8ClNO | Mass Spec | Chemical | MassBank | |
| 4-CHLOROPHENYL ACETATE | C8H7ClO2 | Mass Spec | Chemical | MassBank | |
| 4-CHLOROPHENYL PHENYL ETHER | C12H9ClO | Mass Spec | Chemical | MassBank | |
| 4-CHLOROPHENYLACETIC ACID | C8H7ClO2 | Mass Spec | Chemical | MassBank | |
| 4-CHLOROPHENYLMETHYLCARBINOL | C8H9ClO | Mass Spec | Chemical | MassBank | |
| 4-CYANO-2,5-DIMETHOXY-6-METHYLTROPONE | C11H11NO3 | Mass Spec | Chemical | MassBank | |
| 4-CYANO-2-PHENYL-1-PYRROLINE | C11H10N2 | Mass Spec | Chemical | MassBank | |
| 4-CYANO-4-(2-CYANOETHYL)CYCLOHEXENE | C10H12N2 | Mass Spec | Chemical | MassBank | |
| 4-CYANO-5-METHYL-6-PHENYL-2-(PARA-TOLYL)PERHYDROPYRROLO(3,4-C)PYRROLE-1,3-DIONE (3A,4-CIS-6,6A-CIS) | C21H19N3O2 | Mass Spec | Chemical | MassBank | |
| 4-CYANO-5-METHYL-6-PHENYL-2-(PARA-TOLYL)PERHYDROPYRROLO(3,4-C)PYRROLE-1,3-DIONE (3A,4-CIS-6,6A-TRANS) | C21H19N3O2 | Mass Spec | Chemical | MassBank |