The macroscopic behaviors of materials are determined by interactions that occur at multiple lengths and time scales. Depending on the application, describing, predicting, and understanding these behaviors may require models that rely on insights from atomic and electronic scales. In such cases, classical simplified approximations at those scales are insufficient, and quantum-based modeling is required. In this paper, we study how quantum effects can modify the mechanical properties of systems relevant to materials engineering. We base our study on a high-fidelity modeling framework that combines two computationally efficient models rooted in quantum first principles: Density Functional Tight Binding (DFTB) and many-body dispersion (MBD). The MBD model is applied to accurately describe non-covalent van der Waals interactions. Through various benchmark applications, we demonstrate the capabilities of this framework and the limitations of simplified modeling. We provide an open-source repository containing all codes, datasets, and examples presented in this work. This repository serves as a practical toolkit that we hope will support the development of future research in effective large-scale and multiscale modeling with quantum-mechanical fidelity.

中文翻译：

---

材料力学的量子模拟：DFTB+MBD 框架


材料的宏观行为是由多个长度和时间尺度上发生的相互作用决定的。根据应用的不同，描述、预测和理解这些行为可能需要依赖原子和电子尺度洞察的模型。在这种情况下，这些尺度的经典简化近似是不够的，需要基于量子的建模。在本文中，我们研究量子效应如何改变与材料工程相关的系统的机械性能。我们的研究基于一个高保真建模框架，该框架结合了两个植根于量子第一原理的计算高效模型：密度功能紧束缚（DFTB）和多体色散（MBD）。 MBD 模型用于准确描述非共价范德华相互作用。通过各种基准测试应用程序，我们展示了该框架的功能以及简化建模的局限性。我们提供了一个开源存储库，其中包含本工作中提供的所有代码、数据集和示例。该存储库作为一个实用的工具包，我们希望它能够支持未来在具有量子力学保真度的有效大规模和多尺度建模方面的研究发展。