<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kumar, Viksit</style></author><author><style face="normal" font="default" size="100%">Dongre, Sangram D.</style></author><author><style face="normal" font="default" size="100%">Vandhanam, Aparna</style></author><author><style face="normal" font="default" size="100%">Jadhav, Ashok Badrinarayan</style></author><author><style face="normal" font="default" size="100%">Kumar, Jatish</style></author><author><style face="normal" font="default" size="100%">Babu, Sukumaran Santhosh</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">(Chiro)optical Properties of π-Extended Spiro-Double Carbo[7]helicene</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Physical Chemistry Letters</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2025</style></year><pub-dates><date><style  face="normal" font="default" size="100%">NOV </style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">16</style></volume><pages><style face="normal" font="default" size="100%">11657-11664</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;
	Helical nanographenes are a fascinating class of pi-extended chiral nanocarbons, where structural helicity imparts intrinsic chirality and unique optoelectronic properties to the rigid carbon framework. In this work, we synthesized a hexa-peri-hexabenzocoronene-based pi-extended spiro-double carbo[7]helicene. The helical distortion of the structure was unambiguously confirmed by X-ray crystallography. The optical properties were explored through UV-Vis absorption, fluorescence, and phosphorescence measurements, complemented by density functional theory (DFT) calculations. Remarkably, the pi-extended spiro-double carbo[7]helicene exhibited thermally activated delayed fluorescence (TADF) at room temperature and phosphorescence at low temperatures. Chiral HPLC successfully resolved the enantiomers into three fractions: (PP), (MM), and the meso forms (PM)/(MP), and chiroptical studies of the pure enantiomers revealed a moderately high g lum value of 1.58 x 10-3. Finally, the origin of the observed dissymmetry factors was rationalized by analyzing the transition electric dipole moments (TEDM) and transition magnetic dipole moments (TMDM) derived from time-dependent density functional theory (TD-DFT) calculations.&lt;/p&gt;
</style></abstract><issue><style face="normal" font="default" size="100%">45</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">&lt;p&gt;
	Foreign&lt;/p&gt;
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	5.1&lt;/p&gt;
</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Dongre, Sangram D.</style></author><author><style face="normal" font="default" size="100%">Venugopal, Geethu</style></author><author><style face="normal" font="default" size="100%">Kumar, Viksit</style></author><author><style face="normal" font="default" size="100%">Badrinarayan Jadhav, Ashok</style></author><author><style face="normal" font="default" size="100%">Kumar, Jatish</style></author><author><style face="normal" font="default" size="100%">Babu, Sukumaran Santhosh</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Chiroptical amplification of [7]-helicene nanographene by additional helical chirality</style></title><secondary-title><style face="normal" font="default" size="100%">Angewandte Chemie-International Edition</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">circularly polarised luminescence</style></keyword><keyword><style  face="normal" font="default" size="100%">dissymmetry factor</style></keyword><keyword><style  face="normal" font="default" size="100%">helicene</style></keyword><keyword><style  face="normal" font="default" size="100%">nanographene</style></keyword><keyword><style  face="normal" font="default" size="100%">quantum yield</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2025</style></year><pub-dates><date><style  face="normal" font="default" size="100%">FEB </style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">64</style></volume><pages><style face="normal" font="default" size="100%">e202420767</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;
	Nanographenes have captivated scientific interest since the pioneering discovery of graphene. Recently, attention has shifted towards exploring chiral and nonplanar nanographenes, for their distinct optical, chiroptical, and electronic properties. Despite the growing acceptance of helicenes, the research on inducing helical chirality on pi-extended derivatives to boost chiroptical properties remains unattended. In our study, we introduce a new pi-extended [7]-helicene resulting from the condensation of diamines with 3,6-dibromophenanthrene-9,10-dione, complemented by two hexabenzocoronene arms in the periphery. Notably, the nanographene containing binaphtho-[1,4]diazocine, compared to the corresponding phenazine, exhibits a remarkable average 2.5, 5, and 10-fold enhancements in quantum yield, dissymmetry factor, and brightness, respectively, when measured in five different solvents. These improvements underscore the significance of the induced helical chirality by the antiaromatic binaphtho-[1,4]diazocine in influencing the chiroptical properties of the helical nanographene. Our research represents a significant stride toward unlocking the potential of pi-extended helicenes and lays the groundwork for further exploration in designing and synthesizing new chiral nanomaterials.&lt;/p&gt;
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	Foreign&lt;/p&gt;
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	17&lt;/p&gt;
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