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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
2019-11-07 15:10   生命學院 審核人:   (點擊: )

全校師生:

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.報告會簡介

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).

中文對照:

表面催化化學反應;界面的化學性質敏感地決定了器件的電子和傳輸特性;水的吸附特性決定了材料的腐蝕過程。舉幾個例子就清楚了,許多日常生活現象都依賴于表面的實際原子結構。

實驗上,要分離不同參數的影響,得到感興趣過程的原子分辨率是不容易的。基于量子理論的原子解析理論模型,即所謂的從頭算方法,可以預測材料和表面性質,加深對表面基本過程的理解。

本次講座中將介紹這一領域的幾個應用。氧化物材料是混凝土的主要成分,其與水的相互作用會導致腐蝕。問題是,鋁氧化物的氟化是否能夠保護氧化物免受腐蝕(1)。均相催化劑主要用于實驗室規模的氟化反應,但對于大規模生産,均相催化劑是首選。我們研究了一種新材料acf,其中氟化鋁摻雜了氯化物。這種非晶態材料(2)可以催化各種氟化反應,用密度泛函方法可以研究這種催化的模型反應。

石墨烯因其電子特性而聞名,但其在電子器件中的應用通常與襯底有關。我們研究了石墨烯及其衍生物在不同金屬表面(3,4)上的電子和磁性的變化。然而,化學修飾會顯著改變石墨烯的電子性質。我們研究了非對稱鹵化石墨烯材料(5),該材料在環境條件下可用于co檢測。例如,這些材料可用于太陽能器件中的電荷分離和氰基功能化石墨烯(6)。所有這些研究都采用先進的電子結構方法,以達到與實驗結果相比較的必要精度。這些方法必須進一步改進,其中一種可能是局部相關方法家族,它允許將基于波函數的高精度相關方法應用于擴展系統。我將要介紹的這種方法的應用的一個例子是水分子在碳納米管(7)中的吸附,其中人們發現基于波函數的方法和密度泛函理論的結果有質的不同。

2.歡迎各學院師生前來聽報告。報告會期間請關閉手機或將手機調至靜音模式。

党委學生工作部

生命學院

2019年11月7日

報告人簡介

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學生物研究所所长。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。


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