Adsorption behavior of tin phthalocyanine onto the (110) face of rutile TiO₂

Abstract

The adsorption behavior of tin phthalocyanine (SnPc) molecules on rutile TiO2(110) was studied by scanning tunneling microscopy (STM). Low-temperature STM measurements of single molecules reveal the coexistence of two conformations of molecules on the TiO2 surface. Density functional theory-based simulations (DFT) indicate that the difference originates from the position of the tin atom protruding from the molecule plane. The irreversible switching of Sn-up molecules into the Sn-down conformation was observed either after sample annealing at 200 °C or as a result of tip-induced manipulation. Room-temperature measurements conducted for a coverage of close to a monolayer showed no tendency for molecular arrangement.

Extended iron phthalocyanine islands self-assembled on a Ge(001):H surface

“…However, the need to electronically decouple organic moieties from the underlying substrates directed the attention towards insulators and/or semiconductors. Metal phthalocyanines on semiconducting TiO 2 surfaces have been frequently studied in the context of a future application in photovoltaics [ 58 – 59 ]. A few of the phthalocyanines with different central metal atoms exhibit magnetic properties [ 60 ] and thus attract growing attention.…”

On-Surface Synthesis of Self-Assembled Covalently Linked Wavy Chains with Site-Selective Conformational Switching

“…First, during the covalent coupling reaction only one specific precursor conformation should ideally be present to promote structural homogeneity. Some strategies have been demonstrated to effectively control the molecular conformation, such as the template effect of organometallic intermediates, , new adsorbate surface formed by leaving bromine atoms or distinct substrates, , adjusting molecular concentration, , annealing or tip-induced manipulation, , etc. Alternatively, multiple precursor conformations on surfaces can also be arranged into ordered chains by site-selective conformational switching .…”

Adsorption of Phthalocyanines on Stoichiometric and Reduced Rutile TiO2 (110)

“…22 There are several experimental works related to MPcs adsorption on titania surface by using scanning tunneling microscopy (STM) in a ultrahigh vacuum (UHV) system. [23][24][25][26][27][28][29][30][31][32] Generally, MPcs adsorbed on the most thermodynamically stable (110) face and on the second most stable (011) face of rutile titania such as CoPc/TiO 2 (110), 25 CuPc/TiO 2 (110), 29 FePc/TiO 2 (110), 32 SnPc/TiO 2 (110), 31 metal-free H2Pc/TiO 2 (110), 27 ZnPc/TiO 2 (011), 26 SnPc/TiO 2 (011) 23 and CuPc/(011). 24,30 A few studies about density functional theory (DFT) calculations of MPcs adsorbed onto titania (101) surface 33 because it can be an arduous task for such a big MPc molecules.…”