TiO2 Polymorph
Definition
Titanium dioxide exists as rutile (Raman 143, 447, 612 cm-1) or anatase (Raman 144, 197, 399, 513 cm-1); the polymorph distinguishes premium from lower-grade formulations.
- Rutile Raman peaks
- 143, 447, 612 cm-1
- Anatase Raman peaks
- 144, 197, 399, 513 cm-1
- Distinguishes
- Premium versus lower-grade paint formulations
- Compound
- Titanium dioxide (TiO2) white pigment
Common questions
Why does the choice of TiO2 polymorph matter for paint comparison?+
Rutile and anatase are used in different grades and eras of paint manufacture and have different optical and weathering properties, so identifying the polymorph present can narrow the possible product line or manufacturing period of a paint sample.
Could visible-light examination alone tell rutile from anatase apart?+
No, both appear as ordinary white pigment to the eye. The two polymorphs are distinguished by their Raman spectra, and sometimes by X-ray diffraction, not by any visible colour or optical property under normal examination.
Related terms
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- SWGMAT
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