CAREER: Extending the Range of Applicability of Density-Functional Methods

普渡大学的Adam Wasserman获得了化学部门化学理论、模型和计算方法项目的CAREER奖，他开发和应用了基于密度泛函理论的电子结构方法，扩展了量子化学方法的范围。所研究的方法为开发和测试近似密度泛函提供了一个新的框架，用于精确计算分子的基态和激发态，包括亚稳态。应用包括分子解离，远程电荷转移激发，以及通过分子线的电导-所有这些情况下，需要精确的Kohn-Sham势在新的框架中通过计算适当的分配势来规避，这是一个新的概念，也应该证明从非传统的角度理解化学键是有用的。它的时变扩展将有助于我们对现代光谱学和分子电子学的理解和教学。化学的基本原理是两个成键碎片的能量低于两个分离碎片的能量之和。使用Wasserman教授和他的研究小组正在开发的算法，这两个能量之间的差异可以精确地计算出任何一对碎片。为了整个科学界的利益，他们正在将新的算法实现到广泛可用的大型量子化学代码中。他们还利用普渡大学现有的资源，开发教学工具，以促进电子结构理论领域的科学进展的传播。此外，他们还通过组织促进西班牙裔参与科学研究的科学活动，增加西班牙裔少数民族的参与。

Adam Wasserman of Purdue University is supported by a CAREER award from the Chemical Theory, Models and Computational Methods program in the Chemistry division to develop and apply electronic-structure methods that extend the reach of quantum-chemical approaches based on Density Functional Theory. The methods being investigated provide a new framework for developing and testing approximate density functionals for accurate calculations of ground and excited electronic states of molecules, including metastable ones. Applications include molecular dissociation, long-range charge-transfer excitations, and conductance through molecular wires - all cases where the need of accurate Kohn-Sham potentials is circumvented in the new framework by the calculation of appropriate partition potentials, a novel concept that should also prove useful in understanding chemical bonding from a non-traditional perspective. Its time-dependent extension will facilitate our understanding and teaching of modern spectroscopy and molecular electronics.Underlying most of chemistry is the notion that the energy of two bonded fragments is lower than the sum of the energies of the isolated fragments. The difference between those two energies can be calculated accurately for any pair of fragments using the algorithms that Prof. Wasserman and his research group are developing, supported by this grant. They are implementing the new algorithms into large broadly-available quantum-chemistry codes for the benefit of the scientific community at large. They are also developing pedagogical tools to facilitate the dissemination of scientific advances in the field of electronic-structure theory, using existing resources available at Purdue University. In addition, they are increasing the involvement of Hispanic minorities by organizing scientific events that promote Hispanic participation in science research.