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通过含贵金属纳米粒子的一维、二维有序阵列,可以制备纳米线和纳米膜。利用Materials Studio软件构建了由87个银原子内核化学吸附22根含苯不对称硫醚链(TTOE)形成的含银纳米粒子,在不同的间距条件下构建一维和二维阵列模型。首先考察了模型中链及苯环间相关关系受温度及阵列参数的影响情况。相关性由相关性判据界定。经分析,选用了平行次序参数大于0.6、垂直次序参数小于-0.3以及苯环质心间距小于1.0nm的一组判据。相关性分析结果表明,当温度升高至600K时,所有11个模型中链及苯环间相关性几近消失,说明较高温度下,此纳米粒子及其阵列可能不太适合作为纳米电子器件使用。在升温过程中,间距为4.8nm的一维纳米粒子阵列相关性保持较好,而二维则出现在较大间距情况下。其次,考察了模型中TTOE链平均头尾距(可视为链长,反映链伸展情况)受温度及阵列参数影响情况。模拟结果表明,较低温度下链的平均头尾距随纳米粒子间距减小而增加,而在较高温度下链则呈现出不同的伸展情况,转换区间在(500～600)K之间,这与链及苯环间相关性几近消失的区间相一致。产生这一现象应该是链包裹层能量效应和空间效应共同作用的结果。
Nanowires and nanofilms can be prepared by a one-dimensional, two-dimensional ordered array of noble metal-containing nanoparticles. Materials Studio software was used to construct silver nanoparticles containing 22 benzene-containing asymmetric thioether chains (TTOEs), which were chemically adsorbed by 87 silver atom cores. One-dimensional and two-dimensional array models were constructed under different spacings. Firstly, the influence of temperature and array parameters on the relationship between chain and benzene ring in the model was investigated. Relevance is defined by the criterion of relevance. After analysis, a set of criteria that the parallel order parameter is greater than 0.6, the vertical order parameter is less than -0.3, and the centroid of benzene ring is less than 1.0 nm are selected. The correlation analysis showed that the correlation between the chains and benzene rings nearly disappeared in all 11 models when the temperature was raised to 600K, indicating that the nanoparticles and their arrays may not be suitable as nanoelectronic devices at higher temperatures use. During the heating process, the one-dimensional nanoparticle arrays with 4.8nm spacing maintained better correlation, while two-dimensional appeared at larger spacing. Secondly, the average head-to-tail distance of the TTOE chain in the model (which can be regarded as the length of the chain, reflecting the extension of the chain) is affected by the temperature and the array parameters. The simulation results show that the average head-to-tail distance of the chains increases with the decreasing of the nanoparticle spacing at lower temperature, while the chain shows different stretching at higher temperature, the conversion interval is between (500-600) K, This is consistent with the near-disappearance of the correlation between the chain and the benzene ring. The resulting phenomenon should be the result of the combined effect of the energy and space effects of the chain wrapper.