Highly Ordered p-Xylene Adlayer Formed on Rh(111) in HF Solution:  In Situ STM and Ex Situ LEED

Abstract

Structure of the adlayer of p-xylene on Rh(111) in HF solution was investigated by the complementary use of in situ scanning tunneling microscopy (STM) and ex situ low-energy electron diffraction (LEED). In situ STM images revealed that p-xylene molecules lie flat on the Rh(111) surface, forming a highly ordered adlayer with a c(2 3 × 4)rect structure. High-resolution imaging revealed not only the packing arrangement but also the internal structure of each molecule. Two methyl functional groups at the para position of benzene were clearly discerned. The adlayer structure obtained by LEED was consistent with that determined by in situ STM.

Adlayer of Hydroquinone on Rh(111) in Solution and in Vacuum Studied by STM and LEED

“…3. This structure is different from that of p-xylene on Rh͑111͒, which is c(2) ϫ 4)rect, [11][12][13][14] although both p-xylene and HQ have functional groups at para positions. According to the model in Fig.…”

“…12,13,25 Briefly, cyclic voltammetry and in situ STM were carried out in HF solutions with and without HQ. Ex situ LEED measurements were performed in vacuum using a UHV-EC system after emersing the sample from HF solution containing HQ.…”

Scanning Tunneling Microscopy Determination of Single Nanocrystal Core Sizes via Correlation with Mass Spectrometry

“…25 This structural evolution is presumably the opposite of SAM formation wherein molecules first adsorb to form a low-density lying-down phase followed by conversion to a high-density upright phase as more molecules are added. 28 Although prior STM studies of adsorbed xylenes exist, [29][30][31] none are appropriate for determining the imaged height difference between XDT monolayer phases (i.e., lying down vs standing up). Consequently, we will estimate the height difference by comparison with a well-studied thiolate self-assembled monolayer system: 1,6-mercaptohexanol.…”

In Situ STM Evidence for Adsorption of Rhodamine B in Solution

“…Direct and real space information of bonding and coordination of organic molecules with the substrate was obtained. [14][15][16][17][18][19][20] In the present study, the adsorption of rhodamine B (RB) has been studied by cyclic voltammetry and in situ STM. RB is a typical dye of rhodamine group.…”

“…In situ STM has proved to be a powerful tool in the study of electrochemical interfacial and surface science. , Adsorption of organic molecules on different substrates has been extensively investigated by using STM. Direct and real space information of bonding and coordination of organic molecules with the substrate was obtained. − In the present study, the adsorption of rhodamine B (RB) has been studied by cyclic voltammetry and in situ STM. RB is a typical dye of rhodamine group.…”