• Top library match: tert-Butyl benzoate #12602

1. The sample spectrum indicates a material dominated by aromatic ester functional groups and polyether‑like C–O–C linkages. A strong carbonyl band at 1714 cm⁻¹ is attributable to an ester carbonyl (C=O), and characteristic aromatic C–H out‑of‑plane vibrations appear near 723 and 790 cm⁻¹. The overall pattern closely matches tert‑butyl benzoate (library similarity 86%), but the presence of several bands (e.g., 845, 871, 955 cm⁻¹) that are inconsistent with a pure aromatic ester, together with direct literature evidence of Si–O and carbonate absorptions, suggests the material is not a single pure compound. The spectrum shares many features with a polyether‑ester system, possibly a blend or a polymer containing aromatic ester and ether segments.

• Direct evidence also attributes the 845 cm⁻¹ band to Si–O stretching of Al–Mg–O-H [3], the 871 cm⁻¹ band to carbonate [9], and the 955 cm⁻¹ band to silicon‑oxygen [5], which are incompatible with a single organic ester compound.
• The library match to a specific small molecule conflicts with the inorganic group assignments that appear in multiple literature reports on the same peaks.
• Whether the Si–O and carbonate assignments represent trace inorganic additives, contaminants, or mis‑attributions cannot be resolved from the IR spectrum alone.
• The exact molecular structure—whether a polyester, a polyether‑ester, or a small ester blended with other materials—remains ambiguous.
• The library hit may be a deceiving match because of shared functional groups, not a true identification.

Recommended next steps: Perform GC‑MS or NMR analysis to identify volatile/soluble components and confirm the presence of tert‑butyl benzoate or related esters. Use X‑ray fluorescence (XRF) or SEM‑EDS to check for silicon, phosphorus, or metal ions that might explain the inorganic‑type bands. If the sample is polymeric, additional techniques such as pyrolysis‑GC‑MS or MALDI‑TOF would help elucidate the polymer backbone.