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【学术报告】研究生灵犀学术殿堂第515期之Beate Paulus报告会预告通知

发布时间:2019年11月07日 来源:生命学院 点击数:

全校师生:

我校定于2019年11月25日举办研究生灵犀学术殿堂——Beate Paulus教授报告会,现将有关事项通知如下:

1.报告会简介

报告人:Beate Paulus教授

时 间:2019年11月25日(星期一) 下午14:00(开始时间)

地 点:长安校区数字化大楼102

主 题:Surface Science - An Insight from Theory

内容简介:Chemical reactions are catalyzed at surfaces; electronic and transport properties of devices are sensitively determined by the chemical nature of the interfaces; and adsorption characteristics of water determines the corrosion processes of materials. To name only a few examples it is clear, many daily-life phenomena rely on the actual atomic structure of surfaces.

Experimentally, it is not so easy to separate the influence of different parameters and to get atomic resolution of the processes of interest. Theoretical models, atomically resolved and based on quantum theory, the so-called ab initio methods, can predict material and surface properties and increase the understanding of the elementary processes on surfaces.

This talk will present several applications in this field. Oxide materials are the main constituents of concrete, and their interaction with water leads to corrosion. The question arises, whether the fluorination of aluminum oxides can protect the oxides from corrosion (1). Homogeneous catalysts are mainly used for fluorination reactions in the lab scale, but for large- scale production heterogeneous catalyst are preferred. We investigate a new material named ACF, where an aluminum fluoride is doped with chloride. This amorphous material (2) can catalyze various fluorination reactions, the model reactions of this catalysis can be investigated using density functional methods.

Famous for its electronic properties is graphene, but its usage in electronic devices is very often in connection with substrates. We have investigated the change in electronic and magnetic properties of graphene and its derivatives on different metal surfaces (3,4). However, chemical modification will significantly change the electronic properties of graphene. We investigated asymmetrically halogenated graphene materials (5) that would be sensible for CO detection at ambient conditions. As an example, these materials can be used for example as charge separation in solar devices and cyano-functionalized graphene (6). All these investigations use advanced electronic structure methods to achieve the necessary accuracy to compare with experimental results. These methods must be improved further, one possibility is the family of the local correlation methods, which allow the application of highly accurate wavefunction-based correlation methods to an extended system. One example of the application of such methods that I will present is the adsorption of a water molecule in carbon nanotubes (7), where one finds qualitatively different results for wavefunction-based methods and density functional theory.

References:

(1)J. Wirth, J. Schacht, P. Saalfrank, B. Paulus, J. Phys. Chem. C 120, 9713-9718 (2016).

(2)R. Pandharkar, Ch. Becker, J.H. Budau, Z. Kaawar, B. Paulus Inorganics 6, 124, (2018).

(3)L.E. Marsoner Steinkasserer, B. Paulus, E. Voloshina, Chem. Phys. Lett. 597, 148 (2014).

(4) J.Tesch, et al. Sci. Rep. 6, 23439 (2016).

(5)L.E. Marsoner Steinkasserer, A. Zarantonello, B. Paulus, Phys. Chem. Chem. Phys. 18, 25629, (2016).

(6)L.E. Marsoner Steinkasserer, V. Pohl, B. Paulus, J. Chem. Phys. 148, 084703 (2018).

(7)S. Lei, B. Paulus, S. Li, B. Schmidt, J. Comp. Chem. 37, 1313 (2016).

中文对照:

表面催化化学反应;界面的化学性质敏感地决定了器件的电子和传输特性;水的吸附特性决定了材料的腐蚀过程。举几个例子就清楚了,许多日常生活现象都依赖于表面的实际原子结构。

实验上,要分离不同参数的影响,得到感兴趣过程的原子分辨率是不容易的。基于量子理论的原子解析理论模型,即所谓的从头算方法,可以预测材料和表面性质,加深对表面基本过程的理解。

本次讲座中将介绍这一领域的几个应用。氧化物材料是混凝土的主要成分,其与水的相互作用会导致腐蚀。问题是,铝氧化物的氟化是否能够保护氧化物免受腐蚀(1)。均相催化剂主要用于实验室规模的氟化反应,但对于大规模生产,均相催化剂是首选。我们研究了一种新材料acf,其中氟化铝掺杂了氯化物。这种非晶态材料(2)可以催化各种氟化反应,用密度泛函方法可以研究这种催化的模型反应。

石墨烯因其电子特性而闻名,但其在电子器件中的应用通常与衬底有关。我们研究了石墨烯及其衍生物在不同金属表面(3,4)上的电子和磁性的变化。然而,化学修饰会显著改变石墨烯的电子性质。我们研究了非对称卤化石墨烯材料(5),该材料在环境条件下可用于co检测。例如,这些材料可用于太阳能器件中的电荷分离和氰基功能化石墨烯(6)。所有这些研究都采用先进的电子结构方法,以达到与实验结果相比较的必要精度。这些方法必须进一步改进,其中一种可能是局部相关方法家族,它允许将基于波函数的高精度相关方法应用于扩展系统。我将要介绍的这种方法的应用的一个例子是水分子在碳纳米管(7)中的吸附,其中人们发现基于波函数的方法和密度泛函理论的结果有质的不同。

2.欢迎各学院师生前来听报告。报告会期间请关闭手机或将手机调至静音模式。

党委学生工作部

生命学院

2019年11月7日

报告人简介

Beate Paulus,德国柏林自由大学W3教授,国际知名的理论化学家。1995年于马克斯-普朗克复杂系统物理研究所获得博士学位(导师:Peter Fulde教授)。2007年成为柏林自由大学理论化学W2教授。2011年晋升为W3正教授。曾任柏林自由大学化学生物研究所所长。研究兴趣包括材料科学、表面吸附过程及二维材料的电子结构、主客体化学、氟化学。担任DFG, ERC grants、洪堡基金等函评专家。迄今已发表学术论文155篇,H-index 27。