Phosphate (PO4) — FTIR absorption peaks and assignments

Quick answer

Phosphate (PO4) 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 Phosphate (PO4)

Showing the 30 best-supported peaks of 606 total for Phosphate (PO4).

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

• 960 cm⁻¹ confidence 1.0

  “cm-1 Additional peaks were found in both models at 1,062, 1,053, 1,047, 1,040, and 1,029 b cm-1) cm-1 m The peak width range was restricted to the width of the sample's phosphate peak (at 960 ± 2 1 c Chi-squared is the weighted difference b”

  Awonusi 等 - 2007 - Carbonate assignment and calibration in the raman DOI: 10.1007/s00223-007-9034-0
• 960 cm⁻¹ confidence 1.0

  “5 highlights that the first two IR bands, assigned to the cm-1 cm-1, Mo-O-Mo vibrational modes, are up-shifted from 792 and 870 to 800 and 887 while the last two IR cm-1 Mo=O bands attributed to the and P-O vibrational modes are down-shifte”

  Baibarac 等 - 2019 - Adsorption of 1,4-phenylene diisothiocyanate onto DOI: 10.1038/s41598-019-48314-x
• 873 cm⁻¹ confidence 1.0

  “Thus, the most important requirements of vibration of the hydroxyl group whereas the peaks at 43(cid:1) cm(cid:1)1 cm(cid:1)1 molecular miscibility and homogeneity of the PC/n-HA was .19 1093 and 603 belong to PO In the composite, 42(cid:1)”

  Banerjee 和 Balasubramanian - 2015 - Nanotexturing of PCn-HA nanocomposites by innovat DOI: 10.1039/c4ra15488f
• 1456 cm⁻¹ confidence 1.0

  “LLM confirmed rule peak-group candidate”

  XRD and FTIR study of A&B type carbonated hydroxyapatite extracted from bovine bone DOI: 10.1063/1.5089399
• 1024 cm⁻¹ confidence 1.0

  “LLM confirmed rule peak-group candidate”

  A rapid method for fungal assisted algal flocculation: Critical parameters & mechanism insights DOI: 10.1016/j.algal.2016.10.022
• 1050 cm⁻¹ confidence 1.0

  “LLM confirmed rule peak-group candidate”

  Development of Composite Scaffolds Based on Cerium Doped-Hydroxyapatite and Natural Gums—Biological and Mechanical Properties DOI: 10.3390/ma12152389
• 1084 cm⁻¹ confidence 1.0

  “The vibration around 1232 is assigned to PO antisymmetric stretching of cm-1 2phosphodiesters while the vibration ~1084 is assigned to PO symmetric stretching of phosphodiesters.”

  Fourier transform infrared microspectroscopy detects biochemical changes during C. elegans lifespan DOI: 10.1016/j.vibspec.2019.04.005
• 959 cm⁻¹ confidence 1.0

  “The predominate peak at cm-1 reflection (ATR)/Fourier transform 959 due to the stretching mode infrared (FTIR) and confocal Raman of phosphate was also found in the microspectroscopies were used to Raman spectrum of corneal calcified Taipei”

  Chen 等 - 2006 - Corneal calcification chemical composition of cal DOI: 10.1007/s00417-005-1191-0