Nonequilibrium Molecular Dynamics: Dynamical Consistency Across Scales

在化学系化学理论、模型和计算方法（CTMC）项目的支持下，约翰霍普金斯大学的Rigoberto Hernandez教授和他的团队将致力于在多个尺度上推进描述分子科学的规则。使用模拟和理论来预测和设计化学的一个基本挑战是要求这些系统必须在原子分辨率上指定，在系统功能的尺度上（通常与烧杯或化学精炼厂一样大），以及介于两者之间的一切。电子的粗粒化，允许全原子分子动力学的传播，已经被证明是揭示分子和近十亿原子的集合的性质的关键。Hernandez教授将开发粗粒度表示和运动方程，以准确描述分子指定的解决方案和材料，通过中等尺度的长度和时间，用于从十亿到七万亿原子的系统。Hernandez博士还将通过他对学生、员工、化学学院和更广泛的受众的领导和指导，通过增加化学企业内部的多样性、公平性和包容性，全面推进科学发展。约翰霍普金斯大学的里戈贝托·埃尔南德斯（Rigoberto Hernandez）将致力于推进对传播化学系统的理解和工具，这些化学系统在结构和动态上是一致的，因为可以在每个尺度上精确地描述可观察物及其非平衡行为。具体来说，他的主要工作目标是：(i)利用降维模型表征由宏观尺度扰动驱动的分子到中尺度系统的远平衡动力学；（ii）发展理论来预测非平衡过程中非平衡路径的内在路径，这些路径涉及多个空间和时间尺度的非均匀粒子；（iii）推进复杂溶剂的随机硬核（SHC）模型，对所提出的算法进行结构和动力学一致性的基准测试；并开发一个新的框架，用于近似识别多相化学系统中在多个时间和长度尺度上表现出相互作用层次的途径。Hernandez博士也参与并将继续参与以下工作：(1)拓宽化学动力学理论和计算工具在其开发者之外的应用，(2)在课堂内外的本科生和研究生教育中增加对化学的学习和欣赏，(3)让公众参与，（iv）通过他领导的“多样性公平开放化学合作”（OXIDE）和“学术领导力培训”（ALT）研讨会，帮助研究活跃的化学系的教师多样化。他的研究成果将通过同行评审的出版物、EveryWhereChem上的帖子以及科学和公共讲座广泛传播。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

WIth support from the Chemical Theory, Models and Computational Methods (CTMC) program in the Division of Chemistry, Professor Rigoberto Hernandez of Johns Hopkins University and his team will work to advance the rules describing molecular science at multiple scales. A fundamental challenge to the use of simulation and theory to predict and design chemistry is the requirement that such systems must be specified at atomic resolution, at the scale in which the system functions (generally as large as beaker or a chemical refinery), and everything in between. The coarse- graining of electrons, allowing for the propagation of all-atom molecular dynamics has already proved to be critical in revealing the properties of molecules and assemblies with nearly up to a billion atoms. Professor Hernandez will develop coarse-grained representations and the equations of motion needed to accurately describe molecular-specified solutions and materials through the middle scales in length and time for systems ranging from a billion to a septillion atoms. Dr. Hernandez will also advance science generally through his leadership and mentoring of students, staff, chemistry faculties and broader audiences through approaches increasing diversity, equity and inclusion within the chemical enterprise.Rigoberto Hernandez of Johns Hopkins University will work to advance understanding and tools for propagating chemical systems that are structurally and dynamically consistent in the sense that observables and their non-equilibrium behavior can be accurately and precisely described at every scale. Specifically, the major objectives of his work are to: (i) characterize far-from-equilibrium dynamics of molecular to mesoscale systems driven by macroscale disturbances using reduced-dimensional models; (ii) develop the theory to predict the intrinsic pathways for nonequilibrium pathways in processes involving many particles heterogeneously which is preserved across multiple space and time scales, and (iii) advance the stochastic hard core (SHC) model for complex solvents, benchmark the proposed algorithms for structural and dynamical consistency, and develop a new framework for approximately identifying the pathways in heterogeneous chemical systems exhibiting a hierarchy of interactions at multiple time and length scales. Dr. Hernandez has also been involved and will continue to be involved in efforts to (i) broaden the use of theoretical and computational tools in chemical dynamics beyond its developers, (ii) increase learning and appreciation of chemistry in the education of undergraduate students and graduate students both inside and outside of the classroom, (iii) engage the general public, and (iv) help diversify the faculty in research-active chemistry departments through his direction of the Open Chemistry Collaborative in Diversity Equity (OXIDE) and the Academic Leadership Training (ALT) workshops. His research findings will be disseminated widely through peer-reviewed publications, and postings on EveryWhereChem, and through scientific and public lectures.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.