论文标题
在其第二分子双层预言时，冰的表面自由能的酸碱分量过渡
Transition in the Acid-Base Component of Surface Free Energy of Ice upon the Premelting of its Second Molecular Bilayer
论文作者
论文摘要
冰表面的分子无序发生在273 K的散装熔化温度以下，称为表面预言。最高的分子层开始逐渐在200 K处进行预播，并通过增加分子迁移率的增加与其低摩擦系数有关。第二个分子双层在257 K左右首映，但没有研究将这种过渡与任何宏观现象的变化联系起来。在这里，我们表明，在257.0 $ \ pm $ 0.1 K.表面敏感的总和频率产生光谱谱图突然在257.0 $ \ pm $ 0.1 k中突然变化的热力学工作表明，在PDMS表面或冰球界面的冰上界面上没有分子水平的变化，即在冰上的转变中，该冰的变化，这是冰的变化，该变化的变化是在变化的变化。使用文献中的现有接触角数据，我们表明，这种过渡是由于冰的表面自由能的降低17 $ \ pm $ \ pm $ 2 mj/m $^2 $ 257.0 $ \ pm $ \ pm $ \ pm 0.1 k. $ \ pm 0.1 k。表面能量的变化为各种不可识别的现象提供了一种可能的解释，包括冰上的象征和弗里奇，既有冰象光，又有多种多样的现象。
Molecular disordering of the ice surface occurs below the bulk melting temperature of 273 K, termed surface premelting. The top-most molecular layer begins gradually premelting at 200 K, and has been linked to its low coefficient of friction through an increase in molecular mobility. The second molecular bilayer premelts around 257 K, but no study has linked this transition to a change in any macroscopic phenomena. Here, we show that the thermodynamic work of adhesion between polydimethylsiloxane (PDMS) and ice changes abruptly at 257.0 $\pm$ 0.1 K. Surface-sensitive sum frequency generation spectroscopy shows that there are no molecular level changes at the PDMS surface or the ice-PDMS interface near the transition in adhesion, indicating that the transition arises from changes of the ice surface. Using existing contact angle data in the literature, we show that this transition is due to a decrease in the acid-base component of the surface free energy of ice by 17 $\pm$ 2 mJ/m$^2$ at 257.0 $\pm$ 0.1 K. The change in surface energy provides a possible explanation for a variety of unexplained phenomena seen across the literature including ice adhesion, friction, and the morphology of snowflakes.
