<?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%">Bhowmik, Aritra</style></author><author><style face="normal" font="default" size="100%">Das, Nirmal</style></author><author><style face="normal" font="default" size="100%">Saxena, Ashish Kumar</style></author><author><style face="normal" font="default" size="100%">Mishra, Kamini</style></author><author><style face="normal" font="default" size="100%">Barsu, Nagaraju</style></author><author><style face="normal" font="default" size="100%">Mishra, Manish Kumar</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">From brittle to elastic: substituent effects on mechanical flexibility in aromatic amide crystals</style></title><secondary-title><style face="normal" font="default" size="100%">Chemistry-An Asian Journal</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">crystal engineering</style></keyword><keyword><style  face="normal" font="default" size="100%">Elasticity</style></keyword><keyword><style  face="normal" font="default" size="100%">Mechanical property</style></keyword><keyword><style  face="normal" font="default" size="100%">nanoindentation</style></keyword><keyword><style  face="normal" font="default" size="100%">responsive crystals</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2026</style></year><pub-dates><date><style  face="normal" font="default" size="100%">MAY</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">21</style></volume><pages><style face="normal" font="default" size="100%">e70795</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;
	Mechanical flexibility in molecular crystalline materials represents a compelling paradigm shift from the long-held perception of crystals as inherently brittle solids. Herein, we demonstrate a brittle-to-elastic transition by subtle molecular modification in a pair of structurally analogous aromatic amides; N-[(4-methoxyphenyl)methyl]formamide (N4MFA, Crystal 1) and N-benzylformamide (NBFA, Crystal 2). Despite their close structural similarity, Crystal 1 exhibits brittle fracture under minimal stress, whereas Crystal 2 shows 1D elastic flexibility with reversible bending. Structural, computational, and mechanical analyses reveal that this contrast arises from substituent-controlled supramolecular packing. In Crystal 1, the methoxy (-OCH3) group promotes dense, anisotropic packing, leading to rigidity and fracture under stress. Removing the substituent in Crystal 2 enhances isotropy, pi-pi stacking, and interlocked packing, enabling reversible strain during elastic bending. Nanoindentation, energy framework, and elastic tensor analyses confirm this transition: Crystal 2 shows near-isotropic stiffness (E max/E min = 1.65) and interconnected energy networks, whereas Crystal 1 exhibits pronounced anisotropy (E max/E min = 3.95) and 1D cohesion. Hirshfeld surface analysis supports more balanced contacts in the elastic crystal. This work establishes a direct structure-mechanical correlation, showing that minor chemical modifications can tune flexibility and provide insights to guide the development of adaptive crystalline materials.&lt;/p&gt;
</style></abstract><issue><style face="normal" font="default" size="100%">10</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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	3.2&lt;/p&gt;
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