0000000000073747

AUTHOR

Saqib Rahman

showing 4 related works from this author

Pressure-dependent modifications in the optical and electronic properties of Fe(IO3)3: the role of Fe 3d and I 5p lone–pair electrons

2021

We have determined by means of optical-absorption experiments that Fe(IO3)3 is an indirect band-gap material with a band-gap energy of 2.1 eV. This makes this compound the iodate with the smallest band gap. We also found that under compression the band-gap energy has an unusual non-linear pressure dependence, which is followed by an abrupt and discontinuous decrease of the band gap at 24 GPa. The observed behavior is explained by means of density-functional calculations, which show that the behavior of the band gap is governed by the combined influence of Fe 4d and I 5p lone pair electrons. In addition, the abrupt decrease of the band-gap energy at 24 GPa is a consequence of a first-order s…

Inorganic Chemistrychemistry.chemical_compoundStructural phaseMaterials sciencechemistryCondensed matter physicsBand gapElectrical resistivity and conductivityPressure dependentPressure dependenceLone pairIodateElectronic propertiesInorganic Chemistry Frontiers
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High-Pressure Raman Study of Fe(IO3)3: Soft-Mode Behavior Driven by Coordination Changes of Iodine Atoms

2020

[EN] We report high-pressure Raman spectroscopy studies of Fe(IO3)(3) up to nearly 21 GPa that have been interpreted with the help of density functional theory calculations, which include the calculation of phonon dispersion curves and elastic constants at different pressures. Zero-pressure Raman-active mode frequencies and their pressure dependences have been determined. Modes have been assigned and correlated to atomic movements with the help of calculations. Interestingly, in the high-frequency region, there are several modes that soften under compression. These modes have been identified as internal vibrations of the IO3 coordination polyhedron. Their unusual behavior is a consequence o…

Phase transitionCoordination sphereMaterials sciencePhononmacromolecular substances02 engineering and technologySoft modes010402 general chemistry021001 nanoscience & nanotechnology01 natural sciencesMolecular physics0104 chemical sciencesSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsBrillouin zonesymbols.namesakeGeneral EnergyFISICA APLICADAsymbolsPhysical and Theoretical ChemistryIsostructural0210 nano-technologyDispersion (chemistry)Raman spectroscopyThe Journal of Physical Chemistry C
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Tuning the Photoresponse of Nano‐Heterojunction: Pressure‐Induced Inverse Photoconductance in Functionalized WO 3 Nanocuboids

2019

S.R. and S.S. contributed equally to this work. This work was mainly supported by the Natural Science Foundation of China (Grant No. 11874076), National Science Associated Funding (NSAF, Grant No. U1530402), and Science Challenging Program (Grant No. TZ2016001). D.E. thanks the financial support from Spanish MINECO under Grant No. MAT2016-75586-C4-1-P and from Generalitat Valenciana under Grant Prometeo/2018/123, EFIMAT. The X-ray diffraction measurements were performed at the BL15U1 station, Shanghai Synchrotron Radiation Facility (SSRF) in China. The HP XAS measurements were performed at 20 ID-C, APS, ANL. APS is supported by DOE-BES, under contract no. DE-AC02-06CH11357. The authors grat…

decompressionPhase transitionMaterials scienceBand gapGeneral Chemical Engineeringinverse photoconductivityGeneral Physics and AstronomyMedicine (miscellaneous)02 engineering and technology010402 general chemistryPolaron01 natural sciencesBiochemistry Genetics and Molecular Biology (miscellaneous)Electrical resistivity and conductivityNano-:NATURAL SCIENCES:Physics [Research Subject Categories]General Materials Sciencelcsh:Sciencepolaronsnano‐heterojunctionsbusiness.industryPhotoconductivityGeneral EngineeringHeterojunctionnano-heterojunctions021001 nanoscience & nanotechnologycompression0104 chemical sciencesphase transitionOptoelectronicslcsh:QCharge carrier0210 nano-technologybusinesscharge carriersAdvanced Science
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First-Order Isostructural Phase Transition Induced by High Pressure in Fe(IO3)3

2020

The high-pressure (HP) behavior of Fe(IO3)3 was studied up to 35 GPa using powder X-ray diffraction, infrared micro-spectroscopy, and ab initio density-functional theory calculations. Fe(IO3)3 show...

DiffractionPhase transitionMaterials scienceInfraredAb initio02 engineering and technology010402 general chemistry021001 nanoscience & nanotechnologyFirst order01 natural sciences0104 chemical sciencesSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsCrystallographyGeneral EnergyHigh pressurePhysical and Theoretical ChemistryIsostructural0210 nano-technologyThe Journal of Physical Chemistry C
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