Atomic structure of the continuous random network of amorphous C[(C6H4)2]2, PAF-1

Guanqun Cai; He Lin; Ziqiang Zhao; Jiaxun Liu; Anthony E Phillips; Thomas F Headen; Tristan G A Youngs; Yang Hai; Haolai Tian; Chunyong He; Yubin Ke; Juzhou Tao; Teng Ben; Martin T Dove

arXiv · 2108.06257

Atomic structure of the continuous random network of amorphous C[(C6H4)2]2, PAF-1

Guanqun Cai·He Lin·Ziqiang Zhao·Jiaxun Liu·Anthony E Phillips·Thomas F Headen·Tristan G A Youngs·Yang Hai·Haolai Tian·Chunyong He·Yubin Ke·Juzhou Tao·Teng Ben·Martin T Dove

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Abstract

We demonstrate that the amorphous material PAF-1, C[(C6H4)2]2, forms a continuous random network in which tetrahedral carbon sites are connected by 4,4'-biphenyl linkers. Experimental neutron total scattering measurements on deuterated, hydrogenous, and null-scattering samples agree with molecular dynamics simulations based on this model. From the MD model, we are able for the first time to interrogate the atomistic structure. The small-angle scattering is consistent with Porod scattering from particle surfaces, of the form Q^{-4}, where Q is the scattering vector. We measure a distinct peak in the scattering at Q = 0.45 {\AA}^{-1}, corresponding to the first sharp diffraction peak in amorphous silica, which indicates the structural analogy between these two amorphous tetrahedral networks.

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Guanqun Cai, He Lin, Ziqiang Zhao, Jiaxun Liu, Anthony E Phillips, Thomas F Headen, Tristan G A Youngs, Yang Hai, Haolai Tian, Chunyong He, Yubin Ke, Juzhou Tao, Teng Ben, Martin T Dove. 2021-08-13. Atomic structure of the continuous random network of amorphous C[(C6H4)2]2, PAF-1. https://arxiv.org/abs/2108.06257

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