Malgaretti Paolo, Bafile Ubaldo, Vallauri Renzo, Jedlovszky Pál, Sega Marcello
Forschungszentrum Jülich GmbH, Helmholtz Institute Erlangen-Nürnberg for Renewable Energy (IEK-11), Cauerstr.1, D-91058 Erlangen, Germany.
Consiglio Nazionale delle Ricerche, Istituto di Fisica Applicata "Nello Carrara," I-50019 Sesto Fiorentino, Italy.
J Chem Phys. 2023 Mar 21;158(11):114705. doi: 10.1063/5.0141971.
The response of Newtonian liquids to small perturbations is usually considered to be fully described by homogeneous transport coefficients like shear and dilatational viscosity. However, the presence of strong density gradients at the liquid/vapor boundary of fluids hints at the possible existence of an inhomogeneous viscosity. Here, we show that a surface viscosity emerges from the collective dynamics of interfacial layers in molecular simulations of simple liquids. We estimate the surface viscosity to be 8-16 times smaller than that of the bulk fluid at the thermodynamic point considered. This result can have important implications for reactions at liquid surfaces in atmospheric chemistry and catalysis.
牛顿液体对小扰动的响应通常被认为可以完全由诸如剪切粘度和膨胀粘度等均匀传输系数来描述。然而，在流体的液/气边界处存在强密度梯度，这暗示了可能存在非均匀粘度。在这里，我们表明，在简单液体的分子模拟中，表面粘度源自界面层的集体动力学。在考虑的热力学点，我们估计表面粘度比体相流体的表面粘度小8至16倍。这一结果可能对大气化学和催化中液-气表面的反应具有重要意义。
