Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Langmuir. 2013 Jun 25;29(25):7838-46. doi: 10.1021/la4006983. Epub 2013 Jun 11.
A new ReaxFF reactive force field has been developed to describe reactions in the Ti-O-H system. The ReaxFF force field parameters have been fitted to a quantum mechanical (QM) training set containing structures and energies related to bond dissociation energies, angle and dihedral distortions, and reactions between water and titanium dioxide, as well as experimental crystal structures, heats of formation, and bulk modulus data. Model configurations for the training set were based on DFT calculations on molecular clusters and periodic systems (both bulk crystals and surfaces). ReaxFF reproduces accurately the QM training set for structures and energetics of small clusters. ReaxFF also describes the relative energetics for rutile, brookite, and anatase. The results of ReaxFF match reasonably well with those of QM for water binding energies, surface energies, and H2O dissociation energy barriers. To validate this ReaxFF description, we have compared its performance against DFT/MD simulations for 1 and 3 monolayers of water interacting with a rutile (110) surface. We found agreement within a 10% error between the DFT/MD and ReaxFF water dissociation levels for both coverages.
一种新的 ReaxFF 反应力场已被开发出来，用于描述 Ti-O-H 体系中的反应。ReaxFF 力场参数已被拟合到一个量子力学 (QM) 训练集中，该数据集包含与键离解能、角度和二面角扭曲以及水和二氧化钛之间的反应以及实验晶体结构、生成热和体弹性模量数据相关的结构和能量。训练集的模型构型基于分子簇和周期性系统（包括体晶体和表面）上的 DFT 计算。ReaxFF 准确地再现了 QM 训练集中小团簇的结构和能量。ReaxFF 还描述了金红石、锐钛矿和板钛矿的相对能量学。ReaxFF 的结果与 QM 对水结合能、表面能和 H2O 离解能垒的结果相当吻合。为了验证这种 ReaxFF 描述，我们将其性能与 DFT/MD 模拟进行了比较，比较对象是 1 和 3 单层水与金红石 (110) 表面的相互作用。我们发现，两种覆盖度下，DFT/MD 和 ReaxFF 的水离解水平之间的误差在 10%以内。
