Ordered PbHPO4 nanowires: Crystal structure, energy bands and optical properties from first principles

Shchur, Ya.; Kityk, A. V.

doi:10.1016/j.commatsci.2017.06.008

Cited by 14 publications

(5 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Compared to the bulk silicon, the porosity of Si generally decreases the refractive indices within the whole calculated spectral range and increases the extinction coefficient k in the visible optical region (Figure 8a,b). The same tendency of increasing the extinction coefficient in the visible range at transition from bulk three-dimensional material to the ordered sequence of one-dimensional nano-rods was formerly observed in PbHPO 4 crystal [56]. Moreover, the Si porosity increases the optical anisotropy (n 1 > n 3 ) especially in ultraviolet region and in the range higher than the near ultraviolet one (above 3.0 eV).…”

Section: Optical Propertiessupporting

confidence: 68%

Porous Si Partially Filled with Water Molecules—Crystal Structure, Energy Bands and Optical Properties from First Principles

et al. 2020

Self Cite

View full text Add to dashboard Cite

The paper reports the results on first-principles investigation of energy band spectrum and optical properties of bulk and nanoporous silicon. We present the evolution of energy band-gap, refractive indices and extinction coefficients going from the bulk Si of cubic symmetry to porous Si with periodically ordered square-shaped pores of 7.34, 11.26 and 15.40 Å width. We consider two natural processes observed in practice, the hydroxylation of Si pores (introduction of OH groups into pores) and the penetration of water molecules into Si pores, as well as their impact on the electronic spectrum and optical properties of Si superstructures. The penetration of OH groups into the pores of the smallest 7.34 Å width causes a disintegration of hydroxyl groups and forms non-bonded protons which might be a reason for proton conductivity of porous Si. The porosity of silicon increases the extinction coefficient, k, in the visible range of the spectrum. The water structuring in pores of various diameters is analysed in detail. By using the bond valence sum approach we demonstrate that the types and geometry of most of hydrogen bonds created within the pores manifest a structural evolution from distorted hydrogen bonds inherent to small pores (∼7 Å) to typical hydrogen bonds observed by us in larger pores (∼15 Å) which are consistent with those observed in a wide database of inorganic crystals.

show abstract

Section: Optical Propertiessupporting

confidence: 68%

Porous Si Partially Filled with Water Molecules—Crystal Structure, Energy Bands and Optical Properties from First Principles

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…It is worth noting that the second-harmonic generation was already detected in KDP + AAO nanocomposite [1,2]. Clear manifestation of nanoscale confinement effect in the optical properties of hydrogen bonded PbHPO 4 crystal of KDP type was recently shown in paper [3].…”

Section: Introductionmentioning

confidence: 80%

KH₂PO₄ + Host Matrix (Alumina / SiO₂) Nanocomposite: Raman Scattering Insight

Shchur

Andrushchak

Strelchuk

et al. 2019

2019 21st International Conference on Transparent Optical Networks (ICTON)

Self Cite

View full text Add to dashboard Cite

We report on the synthesis and Raman scattering characterization of composite materials based on the hostnanoporous matrices filled with nanostructured KH 2 PO 4 (KDP) crystal. Silica (SiO 2 ) and anodized aluminium oxide (AAO) were used as host matrices with various pore diameters, inter-pore spacing and morphology. The structure of the nanocomposites was investigated by X-ray diffraction and scanning electron microscopy. Raman scattering reveals the creation of one-dimensional nanostructured KDP inside the SiO 2 matrix. We clearly observed the stretching ν 1 , ν 3 and bending ν 2 vibrations of PO 4 tetrahedral groups in the Raman spectrum of SiO 2 + KDP. In Raman scattering spectra of AAO + KDP nanocomposite, the broad fluorescence background of AAO matrix dominates to a great extent, hindering thus the detecting of the KDP compound spectral response.

show abstract

“…Based on the diffuse neutron scattering, the authors of paper [ 28 ] showed that the intramolecular vibrational mode at ∼8.95 cm

in benzil crystals is coupled with the shearing motion of the hydrogen-bonded network linking the neighboring molecules. It is worth noting that even the much simpler network of hydrogen bonds of KH

-type crystals plays a definitive role in structural-phase transitions, see, e.g., [ 40 , 41 , 42 , 43 , 44 ].…”

Section: Resultsmentioning

confidence: 99%

Nanoarhitectonics of Inorganic–Organic Silica–Benzil Composites: Synthesis, Nanocrystal Morphology and Micro-Raman Analysis

et al. 2023

View full text Add to dashboard Cite

The synthesis of nanosized organic benzil (C6H5CO)2 crystals within the mesoporous SiO2 host matrix was investigated via X-ray diffraction, transmission electron microscopy, Raman spectroscopy, and ab initio lattice dynamics analysis. Combining these methods, we have proved that the main structural properties of benzil nanocrystals embedded into SiO2 host membranes with pore diameters of 6.0, 7.8, 9.4, and 13.0 nm are preserved compared to a bulk benzil crystal. Space confinement has an insignificant impact on the lattice vibrational properties of benzil crystals implanted into the host matrices. The ab initio lattice dynamics calculation of the phonon spectrum in the Brillouin zone center shows the mechanical and dynamical stability of benzil lattice, revealing very low optical frequency of 11 cm−1 at point Γ.

show abstract

Ordered PbHPO4 nanowires: Crystal structure, energy bands and optical properties from first principles

Cited by 14 publications

References 36 publications

Porous Si Partially Filled with Water Molecules—Crystal Structure, Energy Bands and Optical Properties from First Principles

Porous Si Partially Filled with Water Molecules—Crystal Structure, Energy Bands and Optical Properties from First Principles

KH₂PO₄ + Host Matrix (Alumina / SiO₂) Nanocomposite: Raman Scattering Insight

Nanoarhitectonics of Inorganic–Organic Silica–Benzil Composites: Synthesis, Nanocrystal Morphology and Micro-Raman Analysis

Contact Info

Product

Resources

About

Ordered PbHPO4 nanowires: Crystal structure, energy bands and optical properties from first principles

Cited by 14 publications

References 36 publications

Porous Si Partially Filled with Water Molecules—Crystal Structure, Energy Bands and Optical Properties from First Principles

Porous Si Partially Filled with Water Molecules—Crystal Structure, Energy Bands and Optical Properties from First Principles

KH2PO4 + Host Matrix (Alumina / SiO2) Nanocomposite: Raman Scattering Insight

Nanoarhitectonics of Inorganic–Organic Silica–Benzil Composites: Synthesis, Nanocrystal Morphology and Micro-Raman Analysis

Contact Info

Product

Resources

About

KH₂PO₄ + Host Matrix (Alumina / SiO₂) Nanocomposite: Raman Scattering Insight