Scanning tunneling microscope investigations of lead–phthalocyanine on MoS2

Abstract

Monolayers of the nonplanar organic molecule lead-phthalocyanine ͑PbPc͒ on MoS 2 have been prepared by organic molecular beam epitaxy and investigated with video scanning tunneling microscopy. Three different crystallographic phases have been observed. Two of them, the close packed and the rowlike phase, have already been observed in an earlier study of the planar Cu-Pc. With PbPc we have now observed an additional phase, where three close packed rows alternate with one or two isolated single rows. In contrast to Cu-Pc, in submolecularly resolved images the PbPc appear in two different states, with either a dark or a bright center. This is attributed to the nonplanar molecular geometry, which allows the formation of two different adsorption geometries, the Pb above or below the molecular plane. In video sequences the transition from one state into the other could be observed.

Theoretical and experimental comparison of SnPc, PbPc, and CoPc adsorption on Ag(111)

“…This is largely due to their high thermal stability and ease of sublimation, 1 their propensity to form well-ordered assemblies on a variety of solid surfaces, [2][3][4][5][6][7] and their fascinating and tunable ͑opto-͒electronic properties. 8 MPcs have also been the subject of a variety of pioneering single molecule imaging, spectroscopy, and manipulation experiments, ranging from the seminal work of Gimzewski et al 9 and Lippel et al 10 on imaging intramolecular features using the scanning tunneling microscope ͑STM͒ to the elegant experiments of Zhao et al 11 and, more recently, Wang et al 12 where an STM has been used to very precisely modify and engineer the internal structure of individual molecules.…”

Bis(phthalocyaninato)yttrium grown on Au(111): Electronic structure of a single molecule and the stability of two-dimensional films investigated by scanning tunneling microscopy/spectroscopy at 4.8 K

“…The development of scanning tunneling microscopy/spectroscopy (STM/STS) allows a full characterization of the surface assembly and electronic structure of such species on a molecular scale. The first STM observation in this field involved adsorption of CuPc on Cu(100), and was followed by explorationsubstrates [4][5][6][7][8][9][10][11][12][13][14][15][16]. Later on, the characterization of the electronic structure of these molecules became an important topic because molecular orbitals can be detected directly by STS.…”

NEXAFS studies of copper phthaloyanine on Ge(001)‐2 × 1 and Ge(111)‐c(2 × 8) surfaces

“…But this is not the only effect of reduced mobility. On substrates where planar organic molecules are mobile it is generally the case that flat lying, ordered monolayers are formed [17][18][19][20][21][22]. A weaker interaction leads to a better ordered film.…”