Silicon (Si) — FTIR absorption peaks and assignments

Quick answer

Silicon (Si) is usually assigned by looking for a recurring cluster of characteristic peaks rather than one exact textbook number. The table below shows where the literature most often places this group in FTIR, ranked by accumulated evidence.

Characteristic FTIR peaks for Silicon (Si)

Showing the 30 best-supported peaks of 716 total for Silicon (Si).

Possible materials

Spectrum logic

A functional-group assignment becomes more confident when several expected bands appear together. Use this page to find the strongest-supported peaks, then confirm that the same sample exhibits a coherent pattern rather than a single isolated hit.

Real-world usage

These pages are useful for unknown material analysis, peak explanation in reports, polymer troubleshooting, and verifying whether a candidate material family is chemically plausible.

Common mistakes

• Using one functional-group page as a complete material verdict without checking the rest of the spectrum.
• Assuming the strongest band is always the most diagnostic one.
• Forgetting that processing, additives, aging, and mixtures can shift or broaden expected peaks.

Verification advice

Use DSC, GC-MS, or TGA when several material families share similar bands or when mixture effects make the FTIR assignment uncertain.

Literature behind these assignments

• 3429 cm⁻¹ confidence 1.0

  “The FTIR spectra of the cm-1 montmorillonite-carbon nanotube nano filler display bands at 3429, 1076, and 798 which correspond to OH functional groups, Si-O-Si stretching, and Si-O-Si vibration, respectively.”

  Arizka 等 - 2019 - Synthesis and Physical Properties Characterization DOI: 10.1088/1757-899X/546/4/042004
• 1089 cm⁻¹ confidence 1.0

  “FTIR spectra showed peaks at 1089 and cm-1, 801 which corresponded to asymmetric and symmetric O-Si-O.”

  Fabrication of Biogenic Silica Nanostructures from Sorghum bicolor Leaves for Food Industry Applications DOI: 10.1007/s12633-020-00379-4
• 3604 cm⁻¹ confidence 1.0

  “3741cm-1 sorption peaks at 3604 and observed on both treatment of H-BEA is as follows: H-BEA powder was imH-BEA and Ca/H-BEA have been assigned to Si (OH) Al mersed in an aqueous solution of an alkaline earth metal nibridge structure and lo”

  Atoguchi 和 Kanougi - 2004 - Phenol oxidation over alkaline earth metal ion exc DOI: 10.1016/j.molcata.2004.08.020
• 1106 cm⁻¹ confidence 1.0

  “cm(cid:2)1, 1040¨1180 Acknowledgments It shows a weak peak at 1106 which is attributed to the stretching vibration of Si-O.”

  Baek 等 - 2006 - Structural characterization of beta-SiC nanowires DOI: 10.1016/j.msec.2005.09.083
• 1000 cm⁻¹ confidence 1.0

  “In the spectrum peaks are observed cm-1 cm-1 in the region of 1258.88 corresponding to methyl, between 1000 - 1100 a peak cm-1 corresponding to the Si-O-Si bond and a band at 792.10 characteristic of the siloxanes, confirming the presence o”

  Balvín Beltrán 等 - 2020 - Funcionalización del gel de polisiloxano con nanop DOI: 10.1038/srep35446
• 1009 cm⁻¹ confidence 1.0

  “3.3 Topographical analysis Si-O-Si modes.20 breathing The spectra display asymmetric cm(cid:1)1, stretching at 1009 which corresponds to the presence of The topographical investigation of pristine the PC, PC/FAC and PC/GFACwerestudiedbyAFM.”

  Thin film encapsulation of nano composites of polycarbonate (PC) for thermal management systems DOI: 10.1039/c4ra10183a
• 1037 cm⁻¹ confidence 1.0

  “The peak cm-1 at 1037 was due to O-Si-O vibrations [43].”

  Mimosa pudica mediated praseodymium substituted calcium silicate nanostructures for white LED application DOI: 10.1016/j.jallcom.2016.08.064
• 470 cm⁻¹ confidence 1.0

  “cm-1 The absorption bands centered at around 470, 820, 1170, 2180, and 3300 can be assigned to the Si-N symmetric stretching, Si-N asymmetric stretching, N-H bending, Si-H stretching, and NH stretching modes, respectively.”

  Benyahia 等 - 2017 - Evolution of Optical and Structural Properties of DOI: 10.4028/www.scientific.net/JNanoR.49.163