2,5-Diphenyloxazole

2,5-Diphenyloxazole

Names
IUPAC name 2,5-Diphenyloxazole
Other names PPO, DPO, POP
Identifiers
CAS Number	92-71-7 Y
ChemSpider	6838 Y
ECHA InfoCard	100.001.984
EC Number	202-181-3
PubChem CID	7105
CompTox Dashboard (EPA)	DTXSID7059060
Properties
Chemical formula	C15H11NO
Molar mass	221.259 g·mol−1
Appearance	Yellowish powder
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

2,5-Diphenyloxazole (PPO) is an organic scintillator. It is used as a wavelength shifter (also called a "primary shifter" or "fluor"), which means that it converts shorter wavelength light to longer wavelength light. Its output spectrum peaks at 385 nm, which is in the range of UV light.

Latest measurements

The properties of PPO were measured by Cosmic Rays and Particle group at Nazarbayev University. The PPO was dissolved in 1,2,4-trimethylbenzene (PC or pseudocumene) and tested using the Agilent Cary Eclipse spectrophotometer. This is part of the ongoing work and once its published, the reference will be provided. Right now, raw plots with watermark are being uploaded so that there is any data available.

Excitation

The PPO fluorescence is being excited using wavelength from 190 nm to 370 nm. Fluorescence is monitored at 385 nm.

Excitation of PPO with fluorescence measured at fixed wavelength (385 nm)

Fluorescence

The fluorescence spectrum is shown. The PPO being excited at 280 nm (first peak). Can clearly observe the emission peak at 385 nm.

Emission spectrum of PPO excited at 280 nm