Recent theoretical studies inspired by experiments on the Kitaev magnet $α$-RuCl$_3$ highlight the nontrivial impact of phonons on the thermal Hall conductivity of chiral topological phases. Here we introduce mixed mesoscopic-macroscopic devices that allow refined thermal-transport probes of non-Abelian spin liquids with Ising topological order. These devices feature a quantum-coherent mesoscopic region with negligible phonon conductance, flanked by macroscopic lobes that facilitate efficient thermalization between chiral Majorana edge modes and bulk phonons. We show that our devices enable $(i)$ accurate determination of the quantized thermal Hall conductivity, $(ii)$ identification of non-Abelian Ising anyons via the temperature dependence of the thermal conductance, and most interestingly $(iii)$ single-anyon detection through heat-based anyon interferometry. Analogous results apply broadly to phonon-coupled chiral topological orders.
The reactive complex (NSiN)Ir(H)(OTf)(coe) (1; NSiN = bis(8-quinolyl)methylsilyl, coe = cyclooctene) was generated by reaction of the previously reported (NSiN)Ir(H)Cl(coe) with 1 equiv of AgOTf. Addition of Ph3SiH to 1 in benzene led to Si−H bond activation and octane elimination with formation of the α-Ph-migrated, 16-electron product (NSiN)IrPh(SiPh2OTf) (2). The 29Si{1H} NMR resonance of 2 at δ 54.0 indicates iridium silyl character, and X-ray crystallography reveals the presence of a highly distorted triflatosilyl group. In acetonitrile, 1 reacts with various silanes to give stable, cationic Ir(III) complexes of the type [(NSiN)IrSiR3(NCMe)2][OTf] (R = OSiMe3, Et, Ph) or [(NSiN)Ir{SiH(R)Ph}(NCMe)2][OTf] (R = H, Ph) in good yields. Complex 1 is an active catalyst for arylsilane redistribution and for the dehydrogenative silylation of arenes. The cationic, THF complex [(NSiN)Ir(H)(coe)(THF)][B(C6F5)4] (10), a product of the reaction of 1 with 1 equiv of Li(Et2O)3[B(C6F5)4] in THF, is a slower catalyst for silane redistribution and dehydrogenative arene silylation. A series of new iridium phosphine complexes were prepared, including (NSiN)Ir(H)Cl(PMe3) (13), [(κ2-NSiN)Ir(H)(PMe3)3][Cl] (14), and (κ1-NSiN)Ir(H)(Me)(PMe3)3 (15). Treatment of the previously prepared (NSiN)Ir(H)Cl(PPh3) with 1 equiv of LiBEt3H afforded the dihydride complex (NSiN)IrH2(PPh3) (11), which features a hydride ligand in a coordination site trans to the NSiN silyl group. The triflate complex (NSiN)Ir(H)(OTf)(PPh3) (16) was obtained by reaction of (NSiN)Ir(H)Cl(PPh3) with 1 equiv of AgOTf in dichloromethane or by reaction of 1 with 1 equiv of PPh3 in dichloromethane.
▪ Abstract Recently, sum frequency generation (SFG) vibrational spectroscopy has been developed into a powerful technique to study surfaces of polymer materials. This review summarizes the significant achievements in understanding surface molecular chemical structures of polymer materials obtained by SFG. It reviews in situ detection at the molecular level of surface structures of some common polymers in air, surface segregation of small end groups, polymer surface restructuring in water, and step-wise changed polymer blend surfaces. Studies of surface glass transition and surface structures modified by rubbing, plasma deposition, UV light irradiation, oxygen ion and radical irradiation, and wet etching are also discussed. SFG probing of polymer surfaces provides valuable insights into the relations between polymer surface structures and surface properties, which will assist in the design of polymer materials with desired surface properties.
in reasonably good agreement with their value.Moreover, Eq. (5) shows that a is the same whether the reactant is H 2CO or D 2 CO.Applied to the other isotopic variants of this reaction discussed by TRM, the method gives results in substantial agreement with theirs.The slight differences that were found probably arise from small errors in their calculation of vibrational frequencies, I have recalculated these, using their assumed force constants and molecular geometry in the Schachtschneider-Snyder program,6 and obtain vibrational frequencies slightly different from those reported by TRM.
In this work, using quasiconvexity and rank-one convexity conditions in Cosserat elasticity theory, we derive the Maxwell–Eshelby relation for Cosserat bodies with a surface of discontinuity.
© 2016 The Author(s). While the ab initio prediction of the properties of solids and their optimization towards new proposed materials is becoming established, little predictive theory exists as to which metastable materials can be made and how, impeding their experimental realization. Here we propose a quasi-thermodynamic framework for predicting the hydrothermal synthetic accessibility of metastable materials and apply this model to understanding the phase selection between the pyrite and marcasite polymorphs of FeS2. We demonstrate that phase selection in this system can be explained by the surface stability of the two phases as a function of ambient pH within nano-size regimes relevant to nucleation. This result suggests that a first-principles understanding of nano-size phase stability in realistic synthesis environments can serve to explain or predict the synthetic accessibility of structural polymorphs, providing a guideline to experimental synthesis via efficient computational materials design.
