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[Display omitted] • A novel g-C 3 N 4 is developed as efficient selective adsorbent for HgCl 2 and Hg0. • EDD and DOS reveals the binding of g-C 3 N 4 with HgCl 2 and Hg0 is not chemical interaction. • QTAIM and IRI prove the binding depends on van der Waals force. • COHP confirms polyatomic co-binding is responsible for the separation of HgCl 2 and Hg0. • g-C 3 N 4 possesses potential for thermal regeneration. The partitioning of Hg0 and HgCl 2 with selective adsorbent is an essential technology for the mercury continuous emission monitoring system (Hg-CEMS), but the existing adsorbents fail to satisfy the prolonged operational demands of Hg-CEMS due to the irreversible deactivation. This work proposed a novel regenerable selective adsorbent material, g-C 3 N 4 , and delved into the selective adsorption behaviors of Hg0 and HgCl 2 on the g-C 3 N 4 using DFT calculations and experiments. The results show that g-C 3 N 4 has a strong affinity for HgCl 2 , with the binding energy of −0.843 eV, whereas Hg0 is only weakly adsorbed. The electronic structure and weak interaction analysis reveal both Hg0 and HgCl 2 are coupled to g-C 3 N 4 via van der Waals. Further, COHP calculation demonstrates that the adsorption of Hg0 and HgCl 2 on g-C 3 N 4 is essentially the consequence of polyatomic co-binding and the parallel triatomic structure of HgCl 2 , which binds to more C/N atoms, thereby leading to the greater binding energy. The experiments confirmed the effective capability of g-C 3 N 4 in separating Hg0 and HgCl 2 , along with its thermal regeneration potential. It maintains a breakthrough rate of over 98 % for Hg0 and less than 1.6 % for HgCl 2. This work updates the conventional chemical adsorption-based methods for the separation of Hg0 and HgCl 2 , enhances the comprehension of separating both Hg0 and HgCl 2 while concurrently broadening the understanding of the interaction between g-C 3 N 4 and small molecules. [ABSTRACT FROM AUTHOR]

Studies the vibrational modes of C[sub 60] 2CHBr[sub 3] polycrystalline powder by Raman scattering and infrared adsorption techniques. Transfer of a small amount of electrons from the hydrogen atoms to the C[sub 60] molecules; Interactions between CHBr[sub 3] and c[sub 60 molecules.

Self-assembled strategy has been proven to be a promising vista in constructing organized low-dimensional nanostructures with molecular precision and versatile functionalities on solid surfaces. Herein, we investigate by a combination of scanning tunneling microscopy (STM) and dispersion-corrected density functional theory (DFT), the adsorption of tetracene molecules on the silver substrate and the mechanism mediating the self-assembly on Ag(110). As expected, ordered domain is formed on Ag(110) after adsorption with adjacent molecules being imaged with alternating bright or dim pattern regularly. While such behavior has been assigned previously to the difference of molecular adsorption height, herein, it is possible to investigate essentially the mechanism leading to the periodic alternation of brightness and dimness for tetracene adsorbed on Ag(110) thanks to the consideration of Van der Waals (vdW) dispersion force. It is demonstrated that the adsorption height in fact is same for both bright and dim molecules, while the adsorption site and the corresponding interfacial charge transfer play an important role in the formation of such pattern. Our report reveals that vdW dispersion interaction is crucial to appropriately describe the adsorption of tetracene on the silver substrate, and the formation of delicate molecular architectures on metal surfaces might also offers a promising approach towards molecular electronics. [ABSTRACT FROM AUTHOR]

Abstract: The adsorption of FePc on the Ag(110) substrate has been investigated by ultraviolet photoelectron spectroscopy (UPS). The emission features corresponding to the adsorbed organic molecules are located at 1.03, 4.04, 6.53 and 9.22eV below the Fermi level. The features shift in binding energy with increasing the thickness of the organic films indicates an interaction between FePc and the Ag(110) substrate. ARUPS measurements suggest that the molecular plane is nearly parallel to the substrate in the case of a monolayer. The theoretical calculation confirms the experimental results and indicates that the top site is the most stable adsorption configuration. [Copyright &y& Elsevier]

Abstract: The adsorption of perylene on Si (001) surface has been studied by UPS measurement and DFT calculation. With 0.5 monolayer, the perylene molecule adsorbs uprightly with its long axis cross the dimer. At the coverage of 1.0 monolayer, the perylene molecule adsorbs uprightly with its short axis cross the dimer. To increase the separation between the molecules, the molecules adsorb forming a zigzag structure. With coverage increasing, the work function decreases. When the coverage is 1ML, the work function is the minimum. The dipole, formed on the surface, contributes to the change in work function. [Copyright &y& Elsevier]

Abstract: The ordered adsorption structures of FePc on Cu (100) have been studied by scanning tunneling microscopy (STM) and density functional theory (DFT) calculations. With the deposition rate beyond 0.5 ML per min, the FePc molecules are not deposited dispersedly but are deposited as molecular clusters. After the heat treatment (the temperature higher than 420K), the ordered organic structures of p(5×2) or p(2×5) are obtained. The ordered adsorption structures are in the tilt adsorption model. The FePc molecules in the different domains are aligned along the [011] or [] azimuth, respectively, the molecules are tilted. [Copyright &y& Elsevier]

Abstract: The growth of tetracene on SiO2/Si(111) substrate has been studied by ultraviolet photoemission spectroscopy measurements. Seven emission features of the organic material are located at 2.26, 3.56, 4.77, 5.88, 6.98, 8.18 and 9.90eV, respectively, below the Fermi level. The changes in binding energy and work function during the deposition of tetracene molecules on SiO2 substrate indicate an interaction between tetracene molecule and substrate. The interaction between tetracene molecule and substrate is weaker than that between the organic and silicon substrate. The reduction in work function is due to the formation of interface dipole. Based on the density functional theory (DFT) calculation, tetracene molecules are arranged in an upright standing manner with the optimal growth of a small cluster consisting four molecules. [Copyright &y& Elsevier]

Abstract: Deposition of fluorene-1-carboxylic acid molecules on Cu(110) surface has been investigated by LEED and STM. By saturating the surface with one monolayer, a (4×4) pg ordered structure is formed judged from the LEED pattern. STM image shows that the ordered structure is formed in small locally areas. STM results indicate that the molecular aromatic plane of FC-1 is parallel to the substrate. First-principle calculations determined the favorable adsorption site. The adsorption structure presents a chiral property. Two FC-1 molecules, in one unit cell, have their carboxylic groups bonded in identical geometry and equivalent orientation, but with opposite chirality. [Copyright &y& Elsevier]