01781nas a2200289   4500008004100000022001400041245012200055210006900177260007100246300001400317490000600331520076000337653002101097653001301118653003001131653001401161653001501175653001101190100002401201700002501225700002001250700002901270700001801299700002101317700002901338856012401367       2011                        eng d  a1944-824400aIsobutrin from butea monosperma (flame of the forest): a promising new natural sensitizer belonging to chalcone class0 aIsobutrin from butea monosperma flame of the forest a promising   a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJUL  a2440-24440 v33 a<p>In this work, ``isobutrin'', an ecofriendly sensitizer that is extracted from Butea monosperma (commonly known as ``Flame of the Forest'') flowers, is introduced. It is a bright yellow pigment belonging to the chalcone class and is examined as a sensitizer for optoelectronic applications. It is observed that chelation of this dye with Ti ions results into a strong dye-TiO(2) charge transfer (DTCT) band in the visible region. This Ti-Isobutrin chelate is stable, irreversible and its formation is studied using Benesi-Hildebrand plot. The locations of HOMO-LUMO states of the Ti-isobutrin chelate and the corresponding band alignment with TiO(2) are obtained. Also, a thermal stability test revealed that isobutrin is stable above 100 degrees C.</p>10aButea monosperma10achalcone10adye-sensitized solar cell10aisobutrin10asensitizer10aTiO(2)1 aAgarkar, Shruti, A.1 aKulkarni, Roshan, R.1 aDhas, Vivek, V.1 aChinchansure, Ashish, A.1 aHazra, Partha1 aJoshi, Swati, P.1 aOgale, Satishchandra, B.  uhttps://library.ncl.res.in/content/isobutrin-butea-monosperma-flame-forest-promising-new-natural-sensitizer-belonging-001458nas a2200253   4500008004100000022001400041245013900055210006900194260000800263300001400271490000700285520055800292100002400850700002800874700001900902700002000921700002300941700002200964700002300986700003001009700002101039700001801060856012601078       2025                        eng d  a1359-734500aMultifunctional luminogens with synergy of aggregation-induced delayed fluorescence, two-photon absorption and photocurrent generation0 aMultifunctional luminogens with synergy of aggregationinduced de  cJAN  a1447-14500 v613 a<p>
	In this study, we investigated the aggregation-induced delayed fluorescence (AIDF) properties of three luminogens - TN, TA, and TP. Our comprehensive theoretical analysis reveals a significant reduction in the Delta EST in their aggregated or solid-state, activating TADF, on a similar to mu s time-scale. Additionally, these luminogens demonstrate two-photon excited anti-Stokes photoluminescence emission and improved photocurrent generation, attributed to their strong charge transfer characteristics and longer singlet exciton lifetimes.</p>
1 aChatterjee, Abhijit1 aNarayanan, Sundaravalli1 aThorat, Sachin1 aMalik, Ajay, J.1 aAmbhore, Madan, D.1 aNarayanan, Aswini1 aSihag, Anil, Kumar1 aBabu, Sukumaran, Santhosh1 aLahiri, Mayurika1 aHazra, Partha  uhttps://library.ncl.res.in/content/multifunctional-luminogens-synergy-aggregation-induced-delayed-fluorescence-two-photon02229nas a2200241   4500008004100000022001400041245015000055210006900205260000800274300001600282490000700298520136500305100002201670700002401692700001901716700002001735700001901755700001801774700001901792700003001811700001801841856012801859       2025                        eng d  a2041-652000aSteric hindrance modulated efficient thermally activated delayed fluorescence with non-linear optical, ferroelectric and piezoelectric properties0 aSteric hindrance modulated efficient thermally activated delayed  cJUL  a11989-119980 v163 a<p>
	Multi-carbazole-based benzonitrile systems are efficient thermally activated delayed fluorescence (TADF) materials for organic light-emitting diodes (OLEDs). However, they suffer from low PLQY due to the large dihedral angle arising from steric crowding. Addressing this challenge, we demonstrate a potent strategy to engineer steric crowding in this work. To achieve our goal, we have designed three luminogens, namely, CzPHCN, tCzPHCN and Cz2CzPHCN based on phenanthrene-9,10-dicarbonitrile (PHCN), as an acceptor core to minimize the steric hindrance between the donor groups. Among the three luminogens, tCzPHCN exhibits a maximum PLQY of 86% and the highest RISC rate of 3.5 x 105 s-1, the underlying cause being the least dihedral angle of 45.72 degrees and suppressed intermolecular interaction due to the presence of the bulky tert-butyl group. Interestingly, our QM/MM calculations and experimental evidence suggest that the RISC process of both CzPHCN and tCzPHCN takes place via a hot exciton channel. Unlocking a new realm of applications, the unique non-centrosymmetric space group (Cmc21) of CzPHCN offers excellent SHG with a chi(2) value of 0.21 pm V-1 at 1320 nm. In addition to this, the molecule depicts good ferroelectric (PS = 0.32 mu C cm-2), piezoelectric energy harvesting (VOC = 2.8 V) and two-photon absorption properties.</p>
1 aDutta, Madhusudan1 aChatterjee, Abhijit1 aDeka, Nilotpal1 aTanwar, Riteeka1 aMishra, Vishnu1 aSaha, Arindam1 aMandal, Pankaj1 aBoomishankar, Ramamoorthy1 aHazra, Partha  uhttps://library.ncl.res.in/content/steric-hindrance-modulated-efficient-thermally-activated-delayed-fluorescence-non-linear