ADSORPTION OF Br2 ON Na-INTERCALATED LAYERED COMPOUNDS: BROMINE-INDUCED DEINTERCALATION

Abstract

This work refers to a study of the behavior of Br2 adsorbed on Na-intercalated 1T-TaSe2(0001) and TiSe2(0001) surfaces at 100 K and during subsequent warming up to 300 K. The investigation was performed in UHV with LEED and photoemission with synchrotron radiation measurements. At 100 K, the bromine forms molecular multilayers on Na/TaSe2 . The Br2 layer, close to the substrate, interacts weakly with Na near the surface, forming [Formula: see text]. At 300 K, part of the Br 2 overlayer desorbs while the remainder on both 1T-TaSe2 and Tise2 surfaces interacts strongly with Na, leading to deintercalation of Na to the surface in the tendency to form NaBr. The formation of NaBr overlayers causes the transition of the incommensurate [Formula: see text] surface structure of 1T-TaSe2 (0001) to 1×1. ESD from the Br/Na/1T-TaSe2 surface causes the restoration of the [Formula: see text].