Observation of short-range Yu-Shiba-Rusinov states with threefold symmetry in layered superconductor 2H-NbSe2

Yu-Shiba-Rusinov states of Fe adatoms on 2H-NbSe2 show threefold symmetry with short-range decay, in contrast to its imbedded counterpart of sixfold symmetry and long-range decay.

Synthesis and Structures of Three- and Hexa-armed Benzene Derivatives Featuring Lateral Benzoic Ester and Benzoic Acid Functions

The new 1,3,5-tri-substituted and hexa-substituted benzoic methyl esters 1, 3 and benzoic acids 2, 4 have been synthesized. Single-crystal structure determinations of 1 - 3 are reported, which show specific molecular conformations and packings in the crystal. In all structures, the conformation of the molecules deviates considerably from threefold and sixfold symmetry, respectively. Columnar packings are observed in the crystal structures of the esters 1 and 3, stabilized by weak C-H・・・O and C-H・・・π interactions, while the packing of 2 features the formation of supramolecular strands involving the dimerization of the carboxylic acid group.

GROWTH AND ATOMIC STRUCTURE OF ULTRATHIN COBALT LAYERS ON THE Cu(111) FACE CLEAN AND PRECOVERED WITH LEAD

The growth and atomic structure of ultrathin Co layers deposited on the clean Cu(111) face and precovered with about 0.7 ML of Pb were investigated with the use of Auger electron spectroscopy and directional elastic peak electron spectroscopy (DEPES). Auger spectra for the clean Cu (111) face and covered with 1.5 ML of Co indicate the growth of cobalt bilayer islands sunk at one-monolayer depth in the substrate and covered with one monolayer of copper. The ratio of M2,3VV cobalt and copper Auger peak heights increases with cobalt coverage faster for the Pb -precovered Cu(111) face than for the clean surface. DEPES profiles reveal the threefold symmetry of the cobalt layer up to 4.5 ML. For higher coverages, an arrangement of a sixfold symmetry appears, indicating the presence of fcc(111) cobalt domains rotated 60° with respect to the substrate (i.e. growing after a stacking fault abcbac) separated from the abcabc domains by the bcb layer with the hcp structure.