Orientation Bias of Self-Assembled Alkanes and Their Derivatives Under Dynamic Lateral Nanoconfinement Conditions  

作　　者：Conditions Lihua Yu Yuanzhi Xia Tianze Hu Brent Daelemans Steven De Feyter 

机构地区：[1]Department of Chemistry,Division of Molecular Imaging and Photonics,KU Leuven,B-3001 Leuven

出　　处：《CCS Chemistry》2024年第4期1024-1033,共10页中国化学会会刊（英文）

基　　金：funding from KU Leuven(C14/23/090,C14/19/079);the Research Foundation Flanders(FWO)(G082218N,GF9118N);FWO and F.R.S.-FNRS under the excellence of science(EOS)program(grant 30489208);Li-Hua Yu and Tianze Hu gratefully acknowledge financial support through the China Scholarship Council(CSC 201908350094,CSC 202006150018).

摘　　要：Self-assembled molecular networks(SAMNs)formed on crystalline solid substrates result from the spontaneous arrangement of individual molecules into structured patterns.The interaction between molecules and the substrate leads to a nonrandom orientation of SAMNs with respect to the substrate’s lattice.In the case of graphite,the sixfold rotational symmetry of the substrate results in an equivalent rotational degeneracy in the orientation of SAMNs.In this study,we explored how nanoconfinement,that is,the restriction of SAMN formation to nanometersized areas,known as nanocorrals,could impact and potentially alleviate the orientational degeneracy of SAMNs,with emphasis on the influence of molecule symmetry,size,and intermolecular interactions.To this end,we investigated the orientation distribution of n-alkanes and functionalized alkanes within nanocorrals,which were fabricated using scanning tunneling microscopy lithography(nanoshaving).We observed lifting of orientational degeneracy for long alkanes,contrary to shorter alkanes,which did not exhibit this orientation preference.Notably,functionalized alkanes with hydrogen bonding groups demonstrated preferential alignment regardless of length,highlighting the significance of stabilizing intermolecular interactions in the alignment process.This study discussed the underlying principles of the molecular packing process and shed light on the complexity of molecular self-assembly in nanoconfined spaces.

关 键 词：SELF-ASSEMBLY confinement condition nanocorral orientation bias scanning tunneling microscopy 

分 类 号：O62[理学—有机化学]