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The lack of well-documented information in the historical literature on the relationship between war-related expectations and their effects on the bond market in the Ottoman Empire motivates this paper's three contributions. First, this paper is the first empirical study to investigate the break points in the volatility of Ottoman bond prices from a historical point of view. Second, we use the econometric technique developed by Inclan and Tiao (1994) to identify the structural breaks. Last, we use a manually collected dataset from the daily newspapers of the time on daily Ottoman bond prices from 1910 to 1914. Subsequently, we identify five structural break dates, each of them corresponding to important war-related events. When we investigate the commentaries in the Ottoman newspapers, we see that the outbreak of several wars might not have been a surprise for investors in the Ottoman Empire, as reflected by government bond prices. © 2015 Borsa ¯stanbul Anonim Şirketi.

WOS: 000434507900005 ; The lack of well-documented information in the historical literature on the relationship between war-related expectations and their effects on the bond market in the Ottoman Empire motivates this paper's three contributions. First, this paper is the first empirical study to investigate the break points in the volatility of Ottoman bond prices from a historical point of view. Second, we use the econometric technique developed by Inclan and Tiao (1994) to identify the structural breaks. Last, we use a manually collected dataset from the daily newspapers of the time on daily Ottoman bond prices from 1910 to 1914. Subsequently, we identify five structural break dates, each of them corresponding to important war-related events. When we investigate the commentaries in the Ottoman newspapers, we see that the outbreak of several wars might not have been a surprise for investors in the Ottoman Empire, as reflected by government bond prices. Copyright (C) 2015, Borsa Istanbul Anonim Sirketi. Production and hosting by Elsevier B.V.

Using first-principles calculations, we investigate the electronic, mechanical, and optical properties of monolayer WTe2. Atomic structure and ground state properties of monolayer WTe2 (Td phase) are anisotropic which are in contrast to similar monolayer crystals of transition metal dichalcogenides, such as MoS2, WS2, MoSe2, WSe2, and MoTe2, which crystallize in the H-phase. We find that the Poisson ratio and the in-plane stiffness is direction dependent due to the symmetry breaking induced by the dimerization of the W atoms along one of the lattice directions of the compound. Since the semimetallic behavior of the Td phase originates from this W-W interaction (along the a crystallographic direction), tensile strain along the dimer direction leads to a semimetal to semiconductor transition after 1% strain. By solving the Bethe-Salpeter equation on top of single shot G0W0 calculations, we predict that the absorption spectrum of Td-WTe2 monolayer is strongly direction dependent and tunable by tensile strain. ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. was supported by a FWO Pegasus Long Marie Curie Fellowship. S.C. and A.R. acknowledge the financial support from the Marie Curie grant FP7-PEOPLE-2013-IEF Project No. 628876, European Research Council (ERC-2010-AdG-267374), Spanish grant (FIS2013-46159-C3-1-P), Grupos Consolidados (IT578-13), and AFOSR Grant No. FA2386-15-1-0006 AOARD 144088, H2020-NMP-2014 project MOSTOPHOS, GA No. SEP-210187476, and COST Action MP1306 (EUSpec). S.C. acknowledges the support from The Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 115F388. ; Peer reviewed

In this study, we present a theoretical investigation of structural, electronic, and mechanical properties of pentagonal monolayers of carbon (p-graphene), boron nitride (p-B2N4 and p-B4N2), and silver azide (p-AgN3) by performing state-of-the-art first principles calculations. Our total energy calculations suggest feasible formation of monolayer crystal structures composed entirely of pentagons. In addition, electronic band dispersion calculations indicate that while p-graphene and p-AgN3 are semiconductors with indirect bandgaps, p-BN structures display metallic behavior. We also investigate the mechanical properties (in-plane stiffness and the Poisson's ratio) of four different pentagonal structures under uniaxial strain. p-graphene is found to have the highest stiffness value and the corresponding Poisson's ratio is found to be negative. Similarly, p-B2N4 and p-B4N2 have negative Poisson's ratio values. On the other hand, the p-AgN3 has a large and positive Poisson's ratio. In dynamical stability tests based on calculated phonon spectra of these pentagonal monolayers, we find that only p-graphene and p-B2N4 are stable, but p-AgN3 and p-B4N2 are vulnerable against vibrational excitations. ; Flemish Science Foundation (FWO-Vl); Methusalem foundation of the Flemish government; FWO Pegasus Long Marie Curie Fellowship; TUBITAK (114F397)