The effect of heavy atom to two photon absorption properties and intersystem crossing mechanism in aza-boron-dipyrromethene compounds

KARATAY A., Miser M. C., Cui X., Küçüköz B., YILMAZ ALAN H., Sevinç G., ...Daha Fazla

Dyes and Pigments, cilt.122, ss.286-294, 2015 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 122
  • Basım Tarihi: 2015
  • Doi Numarası: 10.1016/j.dyepig.2015.07.002
  • Dergi Adı: Dyes and Pigments
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.286-294
  • Anahtar Kelimeler: Aza-boron-dipyrromethene, Heavy atom effect, Intersystem crossing, Two photon absorption, Ultrafast pump probe spectroscopy, Z-scan technique
  • Bilecik Şeyh Edebali Üniversitesi Adresli: Hayır

Özet

Abstract New aza-boron-dipyrromethene compounds containing bromine atoms at various positions were designed and synthesized to enhance the triplet state population and two photon absorption properties for applications such as two-photon photodynamic therapy, triplet-triplet annihilation up-conversion. Steady state fluorescence and ultrafast pump probe spectroscopy techniques revealed that only 2, 6 positions of aza-boron-dipyrromethene core contribute to triplet state population significantly. Density function theory calculations showed that when bromine atoms introduced to 2, 6 position of aza-boron-dipyrromethene core, singlet and triplet energy levels get closer therefore probability of intersystem crossing increases. Z-scan experiments at 800 nm wavelengths revealed considerably large (610 GM) two photon absorption cross section value with respect to literature for compounds showing intersystem crossing mechanism. The efficient intersystem crossing and enhanced two-photon absorption properties make the investigated aza-boron-dipyrromethene compounds good candidates for two-photon photodynamic therapy application.