• Competing Cation-Anion Interactions and Noncentrosymmetry in Metal Oxide-Fluorides: A First-Principles Theoretical Study 

  Mishra, Abhishek Kumar; Marvel, Michael R.; Poeppelmeier, Kenneth R.; Waghmare, Umesh V. (American Chemical Society, 2014)

  Anomalous Born dynamical charges in perovskite oxides, such as BaTiO3 and KNbO3, are known to be indicators of their tendency to turn polar through cation off-centering and measure of the interaction between d states of ...
• Emergence of Ferroelectricity at a Metal-Semiconductor Transition in a 1T Monolayer of MoS2 

  Shirodkar, Sharmila N.; Waghmare, Umesh V. (American Physical Society, 2014)

  Using a combination of Landau theoretical analysis and first-principles calculations, we establish a spontaneous symmetry breaking of the metallic state of the 1T monolayer of MoS2 that opens up a band gap and leads to an ...
• Evidence of scaling in the high pressure phonon dispersion relations of some elemental solids 

  Srivastava, Divya; Waghmare, Umesh V.; Sarkar, Subir K. (American Institute of Physics, 2014)

  First principles searches are carried out for the existence of an asymptotic scaling law for the zero temperature phonon dispersion relation of several elemental crystalline solids in the high pressure regime. The solids ...
• Composition-dependent photoluminescence and electronic structure of 2-dimensional borocarbonitrides, BCXN (x=1, 5) 

  Moses, Kota; Shirodkar, Sharmila N.; Waghmare, Umesh V.; Rao, C. N. R. (IoP Publishing Ltd, 2014)

  Layered borocarbonitrides BCN and BC5N with a wide difference in composition have been prepared by the urea route. These 2D materials show a significant difference in the photoluminescence spectra, with BCN and BC5N showing ...
• Contribution of stacking fault in lowering the theoretical density of nickel 

  Mittra, Joy; Waghmare, Umesh V.; Arya, Ashok; Dey, Gautam K. (Elsevier Science Bv, 2014)

  It has been shown with the help of first-principle based calculations that the occurrence of stacking fault (SF) changes the density of nickel. Calculations, based upon a twelve {111}-plane supercell of face-centered-cubic ...
• Universal binding energy relation for cleaved and structurally relaxed surfaces 

  Srirangarajan, Aarti; Datta, Aditi; Gandi, Appala Naidu; Ramamurty, U.; Waghmare, Umesh V. (IoP Publishing Ltd, 2014)

  The universal binding energy relation (UBER), derived earlier to describe the cohesion between two rigid atomic planes, does not accurately capture the cohesive properties when the cleaved surfaces are allowed to relax. ...
• The nature of the structural phase transition from the hexagonal (4H) phase to the cubic (3C) phase of silver 

  Chakraborty, Indrani; Shirodkar, Sharmila N.; Gohil, Smita; Waghmare, Umesh V.; Ayyub, Pushan (IoP Publishing Ltd, 2014)

  The phase transition from the hexagonal 4H polytype of silver to the commonly known 3C (fcc) phase was studied in detail using x-ray diffraction, electron microscopy, differential scanning calorimetry and Raman spectroscopy. ...
• Anomalies and synergy in the caloric effects of magnetoelectrics 

  Anand, Shashwat; Waghmare, Umesh V. (IoP Publishing Ltd, 2014)

  We determine isothermal entropy changes (Delta S) associated with electrocaloric, magnetocaloric, and the corresponding multicaloric effects in a model type-I multiferroic system using Landau-Devonshire thermodynamic ...
• Tuning electrochemical potential of LiCoO2 with cation substitution: first-principles predictions and electronic origin 

  Varanasi, Arun Kumar; Bhowmik, Arghya; Sarkar, Tanmay; Waghmare, Umesh V.; Bharadwaj, Mridula Dixit (Springer Heidelberg, 2014)

  With a goal to improve the performance of LiCoO2 as a cathode material in Li-ion batteries, we simulate substitution of various elements (X = Be, Mg, Al, Ga, Si and Ti) for Co using first-principles density functional ...
• Characterization of few-layer 1T-MoSe2 and its superior performance in the visible-light induced hydrogen evolution reaction 

  Gupta, Uttam; Naidu, B. S.; Maitra, Urmimala; Singh, Anjali; Shirodkar, Sharmila N.; Waghmare, Umesh V.; Rao, C. N. R. (American Institute of Physics, 2014)

  Based on earlier results on the photocatalytic properties of MoS2, the 1T form of MoSe2, prepared by lithium intercalation and exfoliation of bulk MoSe2, has been employed for the visible-light induced generation of hydrogen. ...
• Temperature-dependent stability of stacking faults in Al, Cu and Ni: first-principles analysis 

  Bhogra, Meha; Ramamurty, U.; Waghmare, Umesh V. (IoP Publishing Ltd, 2014)

  We present comparative analysis of microscopic mechanisms relevant to plastic deformation of the face-centered cubic (FCC) metals Al, Cu, and Ni, through determination of the temperature-dependent free energies of intrinsic ...
• Adsorption and splitting of H2S on 2D-ZnO1-xNy: first-principles analysis 

  Kouser, Summayya; Waghmare, Umesh V.; Tit, Nacir (Royal Society of Chemistry, 2014)

  We present a thorough analysis of molecular adsorption of a toxic gas, H2S, on pristine, defective and N-substituted 2D-ZnO using first-principles simulations within density functional theory and the parameterized form of ...
• Experimental and first-principles theoretical studies on Ag-doped cuprous oxide as photocathode in photoelectrochemical splitting of water 

  Upadhyay, Sumant; Sharma, Dipika; Singh, Nirupama; Satsangi, Vibha R.; Shrivastav, Rohit; Waghmare, Umesh V.; Dass, Sahab (Springer, 2014)

  Nanostructured thin films of undoped and Ag-doped cuprous oxide were deposited on indium tin oxide-coated glass substrate using simple spray pyrolysis method for their use as photocathode in photoelectrochemical (PEC) cell ...
• Improved Photoelectrochemical Water Splitting Performance of Cu2O/SrTiO3 Heterojunction Photoelectrode 

  Sharma, Dipika; Upadhyay, Sumant; Satsangi, Vibha R.; Shrivastav, Rohit; Waghmare, Umesh V.; Dass, Sahab (American Chemical Society, 2014)

  Nanostructured thin films of Cu2O modified by overlayering SrTiO3 with varying thickness have been studied for the first time as photoelectrode in photoelectrochemical (PEC) water splitting. Effective mass calculations for ...
• First principles analysis of graphene and its ability to maintain long-ranged interaction with H2S 

  Hegde, Vinay I.; Shirodkar, Sharmila N.; Tit, Nacir; Waghmare, Umesh V.; Yamani, Zain H. (Elsevier Science Bv, 2014)

  We determine the chemical activity of (a) carbon site of pristine graphene, (b) Stone-Wales (SW) defect site, and (c) BN-sites of BN-doped graphene towards adsorption of a toxic gas H2S, through comparative analysis based ...
• First-Principles Study of Structure, Vibrational, and Elastic Properties of Stoichiometric and Calcium-Deficient Hydroxyapatite 

  Bhat, Soumya S.; Waghmare, Umesh V.; Ramamurty, Upadrasta (American Chemical Society, 2014)

  Hydroxyapatite (HAp), a primary constituent of human bone, is usually nonstoichiometric with varying Ca/P molar ratios, with the well-known fact that Ca deficiency can cause marked reductions in its mechanical properties. ...
• Strain induced Z(2) topological insulating state of beta-As2Te3 

  Pal, Koushik; Waghmare, Umesh V. (American Institute of Physics, 2014)

  Topological insulators are non-trivial quantum states of matter which exhibit a gap in the electronic structure of their bulk form, but a gapless metallic electronic spectrum at the surface. Here, we predict a uniaxial ...
• High tunability of the work function of (001) surface of ReO3 with O-vacancies: First principles analysis 

  Suchitra; Pan, Jaysree; Waghmare, Umesh V. (American Institute of Physics, 2014)

  Physical and chemical properties of transition metal oxides are central to the emerging field of oxide electronics. However, they are greatly influenced by defects, particularly, oxygen vacancies, which are always present ...
• Structural instabilities and wrinkles at the grain boundaries in 2-D h-BN: a first-principles analysis 

  Singh, Anjali; Waghmare, Umesh V. (Royal Society of Chemistry, 2014)

  The structure of grain boundaries (GBs) or interfaces between nano-forms of carbon determines their evolution into 3-D forms with nano-scale architecture. Here, we present a general framework for the construction of ...
• A stable, quasi-2D modification of silver: optical, electronic, vibrational and mechanical properties, and first principles calculations 

  Chakraborty, Indrani; Shirodkar, Sharmila N.; Gohil, Smita; Waghmare, Umesh V.; Ayyub, Pushan (IoP Publishing Ltd, 2014)

  We report the optical, electronic, vibrational and mechanical properties of a stable, anisotropic, hexagonal (4H) form of silver. First principles calculations based on density functional theory were used to simulate the ...

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