• Top library match: Zinc sulfate #135252

1. The spectrum is dominated by strong silica/siloxane absorptions (Si-O bending at 465 cm⁻¹, Si-O-Si stretching at 1073 and 1099 cm⁻¹, and intertetrahedral Si-O-Si bending at 797 cm⁻¹), indicating a major silicate or silicon dioxide component. The presence of a broad O-H stretch at 3485 cm⁻¹ and a water bending mode at 1645 cm⁻¹ suggests adsorbed moisture or silanol groups. Additionally, weak to moderate bands at 410–493 cm⁻¹ and around 564–600 cm⁻¹ are attributable to metal-oxygen vibrations, compatible with zinc oxide. Bands at 600, 1099, 1117, 1134, 1159, and 1192 cm⁻¹ can be assigned to sulfate S-O stretching and bending modes, consistent with the library-retrieved top candidate zinc sulfate. A peak at 967 cm⁻¹ may arise from SiO₄ tetrahedra or silanol Si-O-H vibrations. The overall chemical evidence suggests a silica-dominant material that incorporates zinc and sulfate species; however, the library match confidence is low, and the exact proportions and phases remain uncertain.

• The library search returned Zinc sulfate with low confidence (0.609 similarity), and the Top-15 contains many silica-dominated entries, indicating that the spectrum is not a pure zinc sulfate reference but likely a mixed-phase or composite material.
• The precise chemical form of zinc and sulfate (e.g., separate zinc oxide and sulfate salt vs. zinc sulfate compound) cannot be confirmed from these data alone.
• The assignment of the 1073 cm⁻¹ band to Si-O-Si stretching relies on analogy with silica literature; direct confirmation would require reference spectra of expected compositions.
• Minor organic contributions (e.g., residual C-H or ester groups) are possible but cannot be reliably ruled out in the absence of strong aliphatic C-H stretching bands.

Recommended next steps: Acquire reference spectra of pure zinc sulfate and zinc oxide in mixtures with silica for direct library comparison. Perform complementary techniques such as XRF or XRD to clarify elemental composition and phase identity. If possible, conduct thermal gravimetric analysis to assess volatile content (water/organics).