Crystal system: orthorhombic
| Band gap (optical, diffuse reflectance), eV |
|---|
Starting materials: distilled HI (aqueous 99.95%), H3PO2 (50% aqueous), SnI2 (synthesized from Sn granules, and I2 (99.8%)),(CH3)2CHNH3I (synthesized from (CH3)2C(H)NH2 (99.5%) and HI)
Product: yellow rectangular needles
Description: Two-necked flask was charged with aqueous HI (6.8 mL, 7.58 M) and aqueous H3PO2 (1.7 mL, 9.14 M). Nitrogen was passed through the liquid to degass the solution. SnI2 (372 mg, 1 mmol) was dissolved in solution, and flask was heated to boiling (~130 ºC) via an oil bath. A bright yellow solution formed under magnetic stirring. Solid (CH3)2CHNH3I (561 mg, 3 mmol) was added to the solution, and the solution was heated to 120º C. Stirring stopped, and the solution cool dot room temperature. Crystals precipitated for 24 hours.
Method: UV-vis absorption (diffuse reflectance)
Description: Diffuse-reflectance measurements were performed and collected at room temperature. A Shimadzu UV-3600 PC double-beam and double monochromator spectrophotometer (operating between 200 to 2500 nm) was used.BaSO4 was used as a nonabsorbing reflectance reference. Generated reflectance v. wavelength data was used to estimate the band gap. The Kubelka-Munk equation α/S = (1-R)^{2}/(2R) was used.
Crystal system: orthorhombic
| Band gap (optical, diffuse reflectance), eV |
|---|
Starting materials: distilled HI (aqueous 99.95%), H3PO2 (50% aqueous), SnI2 (synthesized from Sn granules, and I2 (99.8%)),(CH3)2CHNH3I (synthesized from (CH3)2C(H)NH2 (99.5%) and HI)
Product: Red crystals
Description: Two-necked flask was charged with aqueous HI (6.8 mL, 7.58 M) and aqueous H3PO2 (1.7 mL, 9.14 M). Nitrogen was passed through the liquid to degass the solution. SnI2 (1116 mg, 3 mmol) was dissolved in solution, and flask was heated to boiling (~130 ºC) via an oil bath. A bright yellow solution formed under magnetic stirring. Solid (CH3)2CHNH3I (1683 mg, 9 mmol) was added to the solution, and a pale-yellow precipitate formed within 5 minutes. The temperature was raised to 200º C, and the precipitate turned red. The solution was cooled and precipitate changed back to yellow.
Method: UV-vis absorption (diffuse reflectance)
Description: Diffuse-reflectance measurements were performed and collected at room temperature. A Shimadzu UV-3600 PC double-beam and double monochromator spectrophotometer (operating between 200 to 2500 nm) was used.BaSO4 was used as a nonabsorbing reflectance reference. Generated reflectance v. wavelength data was used to estimate the band gap. The Kubelka-Munk equation α/S = (1-R)^{2}/(2R) was used.