Two-dimensional systems of molecular rotors

“这项奖励是根据2009年美国复苏和再投资法案（公法111-5）资助的。”化学部的分析与表面化学（ASC）项目和材料研究（DMR）部的固态与材料化学（SSMC）项目支持教授们高度协同的合作研究项目。科罗拉多大学博尔德分校的约瑟夫·米歇尔、约翰·普莱斯和克里斯·罗杰斯说。该项目旨在利用分子自组装和吸附特殊合成分子的结合来创造一种新的物质状态，即有序的二维铁电分子偶极子系统。相互作用偶极子的二维晶格被预测显示有序态，包括三角形阵列的铁电态。其中一些相进一步允许存在非常低的障碍，使总偶极矩矢量同步旋转。这种状态的实现将在射频信号处理、快速光调制和数据存储等方面开辟机会。合成的挑战是实现二维结构，其中远程偶极相互作用的强度与局部空间相互作用相当或超过，从而允许出现远程偶极有序。这种有序的转子材料被称为转子电气材料。Michl教授和他的学生将合成转子分子、分子晶体材料和完整的转子阵列。他们还将进行转子分子和组装系统结构的分子动力学计算，为合成工作提供指导和建议。罗杰斯教授和他的学生将使用表面敏感非线性光学和超快光泵/探针技术研究转子阵列的对称性、电光特性和阵列动力学。Price教授和他的学生将利用低频和射频谐振介电光谱研究偶极转子阵列。相关小组将为从本科到研究生阶段的学生提供多学科纳米技术培训。他们还将提供暑期实习机会，让高中教师参与他们的研究，开发网站材料，并向K-12学生提供推广演讲。

"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)." The Analytical and Surface Chemistry (ASC) Program of the Division of Chemistry and the Solid State and Material chemistry (SSMC) Program of the Division of Material Research (DMR) supports the highly synergistic collaborative research project of Profs. Josef Michl, John Price and Chrles Rogers of the University of Colorado at Boulder. This project aims to use a combination of molecular self-assembly followed by adsorption of specially synthesized molecules to create a new state of matter, the ordered two-dimensional ferroelectric molecular dipole system. Two-dimensional lattices of interacting dipoles are predicted to display order states, including ferroelectric states for triangular arrays. Some of these phases further allow the existence of extraordinarily low barriers to synchronized rotation of the total dipole moment vector. The realization of such states would open up opportunities in e.g., rf signal processing, fast light modulation, and data storage. The synthetic challenge is to achieve two-dimensional structures where long-range dipolar interactions are of strength comparable to or exceeding the local steric interactions, thus allowing for the appearance of long range dipole-based order. Such ordered rotor materials are referred to as rotoelectrics. Prof. Michl and his students will synthesize rotor molecules, molecular crystal materials and completed rotor arrays. They will also perform molecular dynamics computations of rotor molecule and assembled system structure, to guide and advise the synthetic work. Prof. Rogers and his students will study rotor array symmetry, electro-optic properties, and array dynamics using surface-sensitive nonlinear optics and ultra-fast optical pump/probe techniques. Prof. Price and his students will study dipolar rotor arrays by low-frequency and radio frequency resonant dielectric spectroscopy. The associated groups will provide training in multidisciplinary nanotechnology to students from undergraduate through post-graduate levels. They will also provide summer internships to involve high school teachers in their research and develop web site materials and outreach presentations to K-12 students.