Interactions of dimethyl sulfoxide with carbon dioxide and water molecules which induce 18 significantly stable complexes are thoroughly investigated. An addition of CO 2 or H 2 O molecules into the DMSOÁ Á Á1CO 2 and DMSOÁ Á Á1H 2 O systems leads to an increase in the stability of the resulting complexes, in which it is larger for a H 2 O addition than a CO 2 . The overall stabilization energy of the DMSOÁ Á Á1,2CO 2 is mainly contributed by the S=OÁ Á ÁC Lewis acid-base interaction, whereas the O − HÁ Á ÁO hydrogen bond plays a significant role in stabilizing complexes of DMSOÁ Á Á1,2H 2 O and DMSOÁ Á Á1CO 2 Á Á Á1H 2 O. Remarkably, the complexes of DMSOÁ Á Á2H 2 O are found to be more stable than DMSOÁ Á Á1CO 2 Á Á Á1H 2 O and DMSOÁ Á Á2CO 2 . The level of the cooperativity of multiple interactions in ternary complexes tends to decrease in going from DMSOÁ Á Á2H 2 O to DMSOÁ Á Á1CO 2 Á Á Á1H 2 O and finally to DMSOÁ Á Á2CO 2 . It is generally found that the red shift of the O − H bond involved in an O − HÁ Á ÁO hydrogen bond increases while the blue shift of a C − H bond in a C − HÁ Á ÁO hydrogen bond decreases when a cooperative effect occurs in ternary complexes as compared to those of the corresponding binary complexes.

Motivated by observations of extreme magnetoresistance (XMR) in bulk crystals of rare-earth monopnictide (RE-V) compounds and emerging applications in novel spintronic and plasmonic devices based on thin-film semimetals, we have investigated the electronic band structure and transport behavior of epitaxial GdSb thin films grown on III-V semiconductor surfaces. The Gd 3+ ion in GdSb has a high spin S=7/2 and no orbital angular momentum, serving as a model system for studying the effects of antiferromagnetic order and strong exchange coupling on the resulting Fermi surface and magnetotransport properties of RE-Vs. We present a surface and structural characterization study mapping the optimal synthesis window of thin epitaxial GdSb films grown on III-V lattice-matched buffer layers via molecular beam epitaxy. To determine the factors limiting XMR in RE-V thin films and provide a benchmark for band structure predictions of topological phases of RE-Vs, the electronic band structure of GdSb thin films is studied, comparing carrier densities extracted from magnetotransport, angle-resolved photoemission spectroscopy (ARPES), and density functional theory (DFT) calculations. ARPES shows a hole-carrier rich topologically-trivial semi-metallic band structure close to complete electron-hole compensation, with quantum confinement effects in the thin films observed through the presence of quantum well states. DFT-predicted Fermi wavevectors are in excellent agreement with values obtained from quantum oscillations observed in magnetic field-dependent resistivity measurements. An electron-rich Hall coefficient is measured despite the higher hole carrier density, attributed to the higher electron Hall mobility. The carrier mobilities are limited by surface and interface scattering, resulting in lower magnetoresistance than that measured for bulk crystals.

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Millions of tons of TiO 2 is being annually produced at the global scale utilizing AlCl 3 as an additive for preferential formation of rutile phase. However, there is contrary data showing that Al doping is in fact working as an inhibitor for the anatase-rutile transformation (ART), raising questions on the role of Al-containing compound in the ART process. In this study, by using density functional theory (DFT) in combination with thermodynamic modeling, the role of Al-doping in bulk and surfaces of TiO 2 , and the coeffect of intrinsic defects on ART at plausible thermodynamic conditions of TiO 2 synthesis have been investigated. Our results show a conditional behavior, i.e., that Al dopant under reduction condition energetically promotes ART by stabilizing rutile bulk phase while it inhibits ART under oxidizing condition. On the surface, substitutional Al inverts surface energies of rutile and anatase phases, hence it promotes the direct formation of rutile from the beginning. This study will provide a better understanding on the role of the Al as a dopant, especially on the TiO 2 surface, as this aspect is not well understood in spite of its wide application in the industry.Titanium dioxide, TiO 2 , has two most significantly important phases: rutile and anatase. During TiO 2 powder synthesis, despite the fact that rutile is the most thermodynamically stable phase, anatase is formed at nanoscale (<14 nm) due to its lower surface energy. [1,2] Anatase is the favored phase for photocatalysis application. [3] However, several studies have recently suggested that polymorphic structures of TiO 2 can give better photocatalytic activity compared to pure anatase by taking advantage of band offset between anatase and rutile. [4][5][6][7][8][9] In addition, rutile, mostly used as a good white pigment in polymers, paints, textiles, or sunscreen creams in cosmetic industry, is the preferred phase in TiO 2 industry with millions of tons of annual consumption. [10,11] This is because rutile has very high refractive index, giving good opacity property. Therefore, to achieve the phaseoptimized performance for a certain application, one need to control the phase composition of TiO 2 .As nanoparticles of TiO 2 are anatase, desired phase can be obtained by promoting or suppressing anatase to rutile transformation (ART) process from the beginning of TiO 2 synthesis or during the post-processing. There are many factors that affect ART process. Introducing impurities or inducing defects (hereafter denoted as defect in general) can be an effective way of ART control. [12] For photocatalytic application, an efficient polymorphic particles with small size and low recombination rate are achievable by choosing a dopant such as Sn 4þ that promotes ART but does not introduce a deep defect level in the band gap. [9,13,14] The role of Al in ART process and its mechanism is still controversial even though Al is widely used in the TiO 2 industry. In industrial chloride process of TiO 2 synthesis for high quality white pigment, AlCl 3 is adde...