Crystal system: orthorhombic
| a: | 8.81400013 Å |
| b: | 8.590999603 Å |
| c: | 27.6439991 Å |
| α: | 90° |
| β: | 90° |
| γ: | 90° |
Starting materials: HI, H3PO2, Ethanol, SnI2, butylammonium iodide (BAI)
Product: dark purple plate-like crystals
Description: In an inert atmosphere, stoichiometric quantities of BAI and SnI2 were added to HI. The solution was heated to 75°C to dissolve the solids and subsequently cooled to 5 °C at a rate of 1.5 °C/hour.
Method: Single-crystal X-ray diffraction
Description: Data were recorded using a Rigaku R-AXIS rapid imaging plate diffractometer with graphite-monochromated Mo Kα radiation (λ = 0.71069 Å).
Crystal system: unknown
| Band gap (fundamental), eV |
|---|
Starting materials: BAI salt, SnI2 salt, stoichiometric ratio 2:1
Product: spin-coated thin film
Description: Starting materials dissolved in 4:1 DMF:DMSO solvent mixture, stirred for 30 min at room temperature. Substrate: quartz substrate with 120 nm gold layer of interdigitated fingers. Precursor solution (0.1-0.3 molar) pipetted onto substrate and spin-coated, 4000 rpm / 30 seconds, targeting film thicknesses 80-300 nm.
Method: Electroabsorption
Description: Films were spin-coated onto interdigitated Au electrode array - 45 micron distance between opposing fingers. Samples mounted in cryostat with Cu wires soldered to opposing electrode stripes. Xe lamp light spectrally filtered, focused on sample and subsequently on UV-enhanced Si photodiode detector. Sample transmission, substrate transmission, and sample electrotransmission were collected in independent scans.Absorbance and electroabsorbance were then calculated from the respective transmissions. The fundamental gap is determined by the crossover point of absorption curves measured under different electric fields in the fundamental band gap region.
Comment: Significantly more detail in paper.
Crystal system: unknown
| Exciton binding energy, eV |
|---|
Starting materials: BAI salt, SnI2 salt, stoichiometric ratio 2:1
Product: spin-coated thin film
Description: Starting materials dissolved in 4:1 DMF:DMSO solvent mixture, stirred for 30 min at room temperature. Substrate: quartz substrate with 120 nm gold layer of interdigitated fingers. Precursor solution (0.1-0.3 molar) pipetted onto substrate and spin-coated, 4000 rpm / 30 seconds, targeting film thicknesses 80-300 nm.
Method: Electroabsorption
Description: Films were spin-coated onto interdigitated Au electrode array - 45 micron distance between opposing fingers. Samples mounted in cryostat with Cu wires soldered to opposing electrode stripes. Xe lamp light spectrally filtered, focused on sample and subsequently on UV-enhanced Si photodiode detector. Sample transmission, substrate transmission, and sample electrotransmission were collected in independent scans.Absorbance and electroabsorbance were then calculated from the respective transmissions. The exciton binding energy arises as the difference of the 1s exciton peak energy observed in conventional absorption and the fundamental gap as determined by the crossover point of absorption curves measured under different electric fields in the fundamental band gap region.
Comment: Significantly more detail in paper.
Crystal system: unknown
| Exciton energy, eV |
|---|
Starting materials: BAI salt, SnI2 salt, stoichiometric ratio 2:1
Product: spin-coated thin film
Description: Starting materials dissolved in 4:1 DMF:DMSO solvent mixture, stirred for 30 min at room temperature. Substrate: quartz substrate with 120 nm gold layer of interdigitated fingers. Precursor solution (0.1-0.3 molar) pipetted onto substrate and spin-coated, 4000 rpm / 30 seconds, targeting film thicknesses 80-300 nm.
Method: Electroabsorption
Description: Films were spin-coated onto interdigitated Au electrode array - 45 micron distance between opposing fingers. Samples mounted in cryostat with Cu wires soldered to opposing electrode stripes. Xe lamp light spectrally filtered, focused on sample and subsequently on UV-enhanced Si photodiode detector. Sample transmission, substrate transmission, and sample electrotransmission were collected in independent scans. Absorbance and electroabsorbance were then calculated from the respective transmissions.
Comment: Significantly more detail in paper.