STM Imaging of Physisorbed Molecules at the Liquid/Graphite Interface

Self-assembly of 5-octadecyloxyisophthalic acid and its coadsorption with terephthalic acid

“…More recently, one important area of STM application is the investigation of the two-dimensional structure, chirality, reactivity and dynamics of organic molecules at the liquid-solid interface [3][4][5][6][7][8][9][10][11][12]. Self-assembled monolayers of long-chain hydrocarbons including n-alkane [5,[13][14][15][16]18], n-alcohol [5,14,[16][17][18][19], n-carboxylic acid [20][21][22][23][24][25][26], carboxylic ester [27], anhydride [28], and other derivatives [16,19,[29][30][31] have been investigated using STM. Among them, n-alcohol and n-carboxylic acid monolayers are made of ordered lamellae, in which two adjacent lamellae are assembled together by hydrogen bonds.…”

Nontrivial Differentiation between Two Identical Functionalities within the Same Molecule Studied by STM

“…Scanning tunneling microscopy (STM) has proven to be a powerful tool in studying physisorbed adlayers of organic molecules on atomically flat conductive surfaces among which graphite is the most popular one. Since the pioneering experiments on physisorbed monolayers of normal alkanes 1,3 and alcohols 2,3 on graphite by STM, considerable knowledge has been acquired on the forces that rule the two-dimensional packing of alkyl-substituted molecules. Both adsorbateadsorbate and adsorbate-substrate interactions control the ordering of these physisorbed monolayers.…”

Bias-Dependent STM Image Contrast Study of Phenyloctadecyl Ethers Physisorbed onto Highly Oriented Pyrolytic Graphite

“…Despite the theoretical constraint that an STM sample be conductive, it was reported that individual molecules in a liquid crystal array formed on a conducting substrate could be resolved by STM − Physisorbed systems such as long-chain alkanes, − functionalized alkanes, − alcohols, − ,− ,, dialkyl-substituted benzenes, − liquid crystals, ,− and dye pigments , have been shown to form close-packed monolayers on highly oriented pyrolytic graphite (HOPG). This well-ordered structure results from van der Waals interactions among long-chain alkyl groups in neighboring molecules and between these groups and the hydrophobic HOPG substrate.…”