Structural change of damaged polyethylene by beta-decay of substituted tritium using reactive force field
Structural change of damaged polyethylene by beta-decay of substituted tritium using reactive force field
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DOI：
10.35848/1347-4065/abbdc8
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发表时间：
2020-10
影响因子：
1.5
通讯作者：
Haolun Li;Susumu Fujiwara;Hiroaki Nakamura;T. Mizuguchi;A. Nakata;T. Miyazaki;Shinji Saito
中科院分区：
文献类型：
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作者：
Haolun Li;Susumu Fujiwara;Hiroaki Nakamura;T. Mizuguchi;A. Nakata;T. Miyazaki;Shinji Saito
氚在DNA或高分子材料上的β衰变引起结构变化的分子机制至今尚未解决，仅通过实验难以研究氚的衰变效应。为了研究氚的衰变效应引起的损伤聚乙烯的结构变化，我们从聚乙烯链中随机去除氢原子，并使用反应力场（ReaxFF）进行分子动力学（MD）模拟。我们采用了两个参数集的ReaxFF和评估其可靠性，通过比较原子力与密度泛函理论计算。在100 K低温下的分子动力学模拟结果表明，聚乙烯的结构随着氢原子的丢失而变得不那么有序。据观察，当两个最近或次最近的碳原子失去氢原子时，将形成双键或环状结构。
The molecular mechanism of structural change caused by the beta-decay of substituted tritium on DNA or polymeric materials is still being unsolved and it is hard to study the decay effect of tritium solely by experiment. In order to study the structural changes of damaged polyethylene caused by the decay effect of tritium, we randomly removed hydrogen atoms from the polyethylene chain and performed molecular dynamics (MD) simulations using the reactive force field (ReaxFF). We adopted two parameter sets of ReaxFF and evaluated their reliability by comparing the atomic forces with density functional theory calculations. The results of MD simulations at a low temperature of 100 K show that the structure of polyethylene will be less ordered when losing more hydrogen atoms. It is observed that a double bond or a cyclic structure will be formed when two carbon atoms, which are the nearest or next-nearest neighbors, lose hydrogen atoms.