The quantitative determination of the S0—T1 absorption in pyrene with the use of intracavity absorption spectroscopy

Abstract

Abstract The spin-forbidden S 0 — T 1 transition of pyrene was quantitatively investigated by applying intracavity absorption spectroscopy. The measurements were carried out in benzolic solutions. The molar decadic extinction coefficient of the 0—0 transition was determined to 6.0 × 10 −4 dm 3 mol −1 cm −1 . The integral absorptivity was calculated to 2.94 × 10 −2 dm 3 mol −1 cm −1 and yielded an intrinsic phosphorescence lifetime of 55.4 s. The intracavity absorptions were measured in a cavity-dumped Rhodamine 6G dye laser. Absorbances were recorded in the range between 8 × 10 −4 and 5 × 10 −6 .