What absorbs at 776 cm⁻¹ in an FTIR spectrum?
Una banda cerca de 776 cm⁻¹ puede apuntar a varios grupos funcionales. A continuación se muestran las asignaciones más probables, clasificadas por cuánta evidencia publicada respalda cada una — cada una trazable a literatura (DOI) y validada de forma cruzada con nuestros más de 130,000 espectros de referencia y grafo de conocimiento.
Backed by 8 cited sources
Respuesta rápida
A band near 776 cm⁻¹ is usually interpreted by checking which functional groups repeatedly co-occur there in the literature, then confirming at least one or two additional peaks in the same sample. This page ranks those assignments by accumulated evidence rather than by a single fixed textbook rule.
Posibles asignaciones de grupos funcionales
| Grupo funcional | Hechos de respaldo | Fuentes citadas | Confianza máxima |
|---|---|---|---|
| Silicon-oxygen (Si-O) | 5 | 5 | 1,0 |
| Silicon (Si) | 3 | 3 | 1,0 |
| Metal oxygen | 1 | 1 | 1,0 |
| Siloxane (Si-O-Si) | 1 | 1 | 1,0 |
| Carboxyl (COOH) | 1 | 1 | 1,0 |
| Secondary amine | 1 | 1 | 1,0 |
| N h | 1 | 1 | 1,0 |
| Ester | 1 | 1 | 1,0 |
| Methyl | 1 | 1 | 1,0 |
| Alkyl C-H | 1 | 1 | 1,0 |
| Phosphate (PO4) | 1 | 1 | 1,0 |
| Aromatic ring | 1 | 1 | 0,8 |
La clasificación refleja la evidencia acumulada de la literatura, no una única regla autorizada. Siempre confirme según el contexto de su muestra.
Materiales posibles
| Material | Picos de apoyo | Grupos superpuestos | Fuentes citadas |
|---|---|---|---|
| NiO | 776, 1006, 1450 | Metal oxygen | 1 |
Los materiales se muestran solo cuando el mismo grupo de literatura respalda esta banda y al menos un pico característico adicional.
Lógica de espectro
This band becomes meaningful only when read with its neighboring peaks. In practice, analysts first look at the assignments above, then check whether the same sample also shows other peaks expected for the same structural motif. A lone band near 776 cm⁻¹ is usually not enough for material identification by itself.
Uso en el mundo real
Este tipo de consulta es común en la identificación de polímeros, cribado de plásticos desconocidos, resolución de problemas de control de calidad, verificación de materiales reciclados y revisión de asignación de picos respaldada por la literatura.
Errores comunes
- Tratar una banda aislada como prueba de un material sin verificar al menos uno o dos picos de apoyo.
- Ignorando superposición: múltiples grupos funcionales pueden contribuir cerca del mismo número de onda.
- Omitir la validación cuando los aditivos, las mezclas, la oxidación o la contaminación puedan distorsionar el espectro.
Consejo de verificación
Cuando persista la ambigüedad, valide la hipótesis con DSC, GC-MS o TGA, especialmente para mezclas, muestras degradadas y polímeros rellenos.
Literatura detrás de estas asignaciones
-
Phosphate (PO4) confianza 1,0
“The cm-1, assignments of the phosphate related peaks are as follows: P-O stretching at 776 P-O-C cm-1,”
An appraisal of the thermal decomposition mechanisms of ILs as potential lubricants DOI: 10.1002/ls.1457 -
Alkyl C-H confianza 1,0
“in vitro duced during incubation is based on methyl ester of cm-1, Produced CLA showed a weak peak at 776 which fatty acid by GC analysis (Devillard et al.”
Optimization of food-grade medium for co-production of bioactive substances by Lactobacillus acidophilus LA-5 for explaining pharmabiotic mechanisms of probiotic DOI: 10.1007/s13197-020-04894-5 -
N h confianza 1,0
“Moreover, it is worth mentioning that F8815 has only primary amino groups as proved by the pair of peaks at 806 and 776 cm-1 cm-1 (NH bending, inset) [36], and the relative strong band at 1639 (NH stretching).”
Bellido-Aguilar 等 - 2019 - Effect of a fluoroalkyl-functional curing agent on DOI: 10.1016/j.surfcoat.2019.02.006 -
Carboxyl (COOH) confianza 1,0
“The band cm-1 cm-1 at 776 was characterized as typical for guluronic acid [33] as well as the 791 cm-1 C.”
Soluble Extracellular Polymeric Substances Produced by Parachlorella kessleri and Chlorella vulgaris: Biochemical Characterization and Assessment of Their Cadmiumand Lead Sorption Abilities DOI: 10.3390/molecules27217153 -
confianza 1,0
“was observed with a peak at 1270 cm-1, and the absorption bands related to the stretching vibrations of the Si-C bond and/or the stretching vibrations of the Si-O bond were observed at 776 cm-1 [35].”
Organic Bio-Based Aerogel from Food Waste: Preparation and Hydrophobization DOI: 10.3390/gels8110691 -
Silicon (Si) confianza 1,0
“cm(cid:4)1 range [39, 40], whereas the band at 776 was the initial substitution of NiO/ CaO, the absorption related to the Si-O-Si symmetric stretches of nonedge exhibited gradual red shift (shift longer wavebridging oxygen atoms between te”
Impact of high NiO content on the structural, optical, and dielectric properties of calcium lithium silicate glasses DOI: 10.1007/s10854-022-08045-8 -
confianza 1,0
“A new peak at 776 assigned to the Mn-O bond was found in cm-1 MnDBC, F 1M 3DBC, and F 3M 1DBC, while a new peak at 558 belonging to the Fe-O bond was found in FDBC, F 1M 3DBC, and F 3M 1DBC, which illustrated the formation of Fe oxides, Mn”
Liang 等 - 2022 - Adsorption of Atrazine by Fe-Mn-Modified Biochar DOI: 10.3390/agronomy12123097 -
Silicon (Si) confianza 1,0
“Aromatic ring substitution is seen at 879 and 776 cm-1 Si-O 1425 region includes C stretching of heteroaromatic [57, 58].”
Biochar from co-pyrolysis of urban organic wastes—investigation of carbon sink potential using ATR-FTIR and TGA DOI: 10.1007/s13399-020-01000-9
¿Tiene un espectro con esta banda?
Cargue su espectro FTIR y obtenga un informe de interpretación completo — asignaciones de picos con citas bibliográficas, coincidencias de librerías y una cadena de evidencia con calificación de confianza — en segundos.