Molecular Control over the Mechanism of Crystal Growth

晶体生长机制的分子控制

• 批准号: 1709370
• 负责人: James Martin
• 金额: $ 40万
• 依托单位: North Carolina State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-07-01 至 2021-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1709370&HistoricalAwards=false
• 关键词: Molecular; Control; over; Mechanism; Crystal

Non-technical Abstract:Control of crystalline structure is important to the application of materials, whether to control the activity of pharmaceuticals or the electronic conductivity of advanced materials. However, deciphering the physical/chemical processes that determine growth of specific crystal structures is complex. This project systematically measures the influence of molecular shape and the strength of intermolecular interactions on the kinetics of crystal growth to investigate molecular level control of the mechanism of melt crystallization. In addition to advancing the fundamental science, this work is invaluable to all fields of science for which crystal growth is critical, such as polymers, pharmaceuticals, food products, geology, and atmospheric science. In addition, professional development for high school chemistry teachers is made available across the state of North Carolina. This discipline based professional development helps teachers shift curricula from a standardized test-based content/algorithm focus to critical-thinking/problem-solving based teaching and learning.Technical Abstract:The research supported by this award uniquely presents a melt crystallization strategy that directly probes the influence of intrinsic factors of molecular shape and intermolecular forces on the mechanism of crystal growth. Experimental measurement of the crystallization kinetics of oligoacenes and alkylammonium metal halide salts, as a function of the number of aromatic rings and length of alkyl chains, respectively, is being used to probe the impact of molecular anisotropy and crystal dimensionality on the rate of crystallization. Comparative kinetic measurements from isotropic vs. oriented melts of liquid crystals is utilized to articulate the impact of molecular pre-orientation on the rate of crystallization. Also, the crystallization kinetics across the family of substituted benzenes creates a geometric and energetic matrix with which to evaluate functional group effects. The PI's recent discovery of Transition Zone Theory, the condensed matter analog of Eyring's transition state theory, enables for the identification of entropic and enthalpic activation parameters of crystallization reactions. This award facilitates a continuing offering of the summer teacher workshops, and also supports hiring a high school chemistry teacher to work with the PI during summers to write and publish components of this professional development, which affords greater dissemination of the problem-solving/discovery based materials.

非技术摘要：晶体结构的控制对于材料的应用非常重要，无论是控制药物的活性还是先进材料的电子导电性。 然而，破译决定特定晶体结构生长的物理/化学过程是复杂的。 本项目系统地测量分子形状和分子间相互作用强度对晶体生长动力学的影响，以研究熔体结晶机理的分子水平控制。 除了推进基础科学之外，这项工作对于晶体生长至关重要的所有科学领域都是非常宝贵的，例如聚合物，制药，食品，地质学和大气科学。此外，高中化学教师的专业发展是整个北卡罗来纳州提供。这种基于学科的专业发展帮助教师将课程从标准化的基于测试的内容/算法焦点转移到基于批判性思维/解决问题的教学和learning.Technical Abstract：该奖项支持的研究独特地提出了一种熔融结晶策略，直接探讨了分子形状和分子间力的内在因素对晶体生长机制的影响。实验测量低聚并苯和烷基铵金属卤化物盐的结晶动力学，分别作为芳环数量和烷基链长度的函数，用于探索分子各向异性和晶体维度对结晶速率的影响。从各向同性与取向的液晶熔体的比较动力学测量被用来阐明分子预取向对结晶速率的影响。此外，整个家庭的取代苯的结晶动力学创建一个几何和充满活力的矩阵，以评估官能团的影响。 PI最近发现的过渡区理论，凝聚态模拟Eyring的过渡态理论，使熵和结晶反应的活化参数的识别。该奖项有助于继续提供暑期教师研讨会，并支持聘请高中化学教师在暑期与PI合作，撰写和出版本专业发展的组成部分，从而更好地传播基于解决问题/发现的材料。

项目成果

A Nonlinear, “Sticky” Web of Study for Chemistry: A Graphical Curricular Tool for Teaching and Learning Chemistry Built upon the Interconnection of Core Chemical Principles

非线性、粘性的化学研究网络：基于核心化学原理互连的化学教学图形化课程工具

• DOI: 10.1021/acs.jchemed.7b00878
• 发表时间: 2018
• 期刊: Journal of Chemical Education
• 影响因子: 3
• 作者: Martin, James D.;Nock, Katherine A.
• 通讯作者: Nock, Katherine A.

Reply to “A Comparison of the Stochastic and Deterministic Approaches in a Nucleation–Growth Type Model of Nanoparticle Formation”

回复“成核过程中随机方法和确定性方法的比较”纳米粒子形成的生长类型模型

• DOI: 10.1021/acs.chemmater.1c01690
• 发表时间: 2021
• 期刊: Chemistry of Materials
• 影响因子: 8.6
• 作者: Martin, James D.

K-space algorithmic reconstruction (KAREN): a robust statistical methodology to separate Bragg and diffuse scattering

• DOI: 10.1107/s1600576719017060
• 发表时间: 2020-02
• 期刊: Journal of Applied Crystallography
• 影响因子: 6.1
• 作者: James Weng;Eric D. Dill;James D. Martin;R. Whitfield;C. Hoffmann;F. Ye

Transition Zone Theory Compared to Standard Models: Reexamining the Theory of Crystal Growth from Melts

• DOI: 10.1021/acs.jpcc.0c03003
• 发表时间: 2020-08-27
• 期刊: JOURNAL OF PHYSICAL CHEMISTRY C
• 影响因子: 3.7
• 作者: Martin, James D.;Hillis, Berkley G.;Hou, Feier
• 通讯作者: Hou, Feier

Particle Size Is a Primary Determinant for Sigmoidal Kinetics of Nanoparticle Formation: A “Disproof” of the Finke–Watzky (F-W) Nanoparticle Nucleation and Growth Mechanism

粒径是纳米颗粒形成 S 形动力学的主要决定因素：Finke Watzky (F-W) 纳米颗粒成核和生长机制的“反证”

• DOI: 10.1021/acs.chemmater.9b02839
• 发表时间: 2020
• 期刊: Chemistry of Materials
• 影响因子: 8.6
• 作者: Martin, James D.