Stretching Vibration Mode Research Articles

Characterization of Acetonitrile Isotopologues as Vibrational Probes of Electrolytes.

Acetonitrile has emerged as a solvent candidate for novel electrolyte formulations in metal-ion batteries and supercapacitors. It features a bright local C≡N stretch vibrational mode whose infrared (IR) signature is sensitive to battery-relevant cations (Li+, Mg2+, Zn2+, Ca2+) both in pure form and in the presence of water admixture across a full possible range of concentrations from the dilute to the superconcentrated regime. Stationary and time-resolved IR spectroscopy thus emerges as a natural tool to study site-specific intermolecular interactions from the solvent perspective without introducing an extrinsic probe that perturbs solution morphology and may not represent the intrinsic dynamics in these electrolytes. The metal-coordinated acetonitrile, water-separated metal–acetonitrile pair, and free solvent each have a distinct vibrational signature that allows their unambiguous differentiation. The IR band frequency of the metal-coordinated acetonitrile depends on the ion charge density. To study the ion transport dynamics, it is necessary to differentiate energy-transfer processes from structural interconversions in these electrolytes. Isotope labeling the solvent is a necessary prerequisite to separate these processes. We discuss the design principles and choice of the CD313CN label and characterize its vibrational spectroscopy in these electrolytes. The Fermi resonance between 13C≡N and C–D stretches complicates the spectral response but does not prevent its effective utilization. Time-resolved two-dimensional (2D) IR spectroscopy can be performed on a mixture of acetonitrile isotopologues and much can be learned about the structural dynamics of various species in these formulations.

Investigated coherent anti-Stokes Raman scattering in the process of cascaded stimulated Raman scattering in liquid and ice-Ih D2O.

Stimulated Raman scattering (SRS) of liquid and ice-Ih D2O was investigated using a pulsed Nd:YAG laser with a wavelength of 532nm. The high-order Stokes peaks and corresponding anti-Stokes SRS [Coherent Anti-Stokes Raman Spectroscopy (CARS)] peaks were obtained. Two symmetric and antisymmetric Raman modes of stretching vibrations were observed in liquid D2O, while only a symmetric stretching vibration mode was observed in ice-Ih D2O. Pure Stokes SRS is always collinear with the pump beam along the axial direction. Some ring-like Stokes SRS and CARS shifts, which originate from four-wave mixing processes, can also be observed only in the forward direction along with different angles meeting the phase-matching criteria, respectively. Simultaneously, the temporal behavior of SRS in liquid and ice-Ih D2O was examined, and the temporal waveforms of the pump laser pulse, transmitted pump pulse, and the forward SRS pulse were measured. In both cases, SRS was the dominant contributor to stimulated scattering. However, the efficiency values drastically decreased due to the self-termination behavior of SRS in liquid D2O, which arose from the thermal self-defocusing of both the pump beam and the SRS beam, owing to the Stokes shift-related opto-heating effect. In contrast, for the SRS process in ice-Ih D2O, the thermal self-defocusing influence was negligible, benefitting from a much greater thermal conductivity and a higher conversion efficiency of SRS generation retained under both of the conditions.

Green and cost-effective synthesis of zinc oxide thin films by L-ascorbic acid (AA) and their potential for electronics and antibacterial applications

The evolution of eco-friendly, green route and cheap technology for synthesizing nanostructured zinc oxide (ZnO) thin films using plant extracts is a promising choice because such materials present a widespread potential for numerous technological applications. This study proposes the green and cost-effective technique to synthesize stable ZnO thin films using a good reducing agent and facilitating many natural L-ascorbic acids (AA) metabolic reactions capacity. The influence of AA concentrations in the starting bath solution on ZnO samples' structural, morphological, electrical and antibacterial performances has been reported in detail. The main physical characteristics of the ZnO materials were improved by supplementing of reducing and capping agents AA. Average particle size varies with the adding AA from 58.29 to 48.68 nm and also thickness of these films was decreased from 0.82 to 0.44 μm. Also, it was seen that, the presence of AA in the bath solution significantly affected the absorption process and causes a morphological alteration due to the reaction between Zn2+ and AA during the deposition process. FTIR transmittance spectra of bare ZnO presented that a transmittance peak about 886 cm−1 and 748 cm−1 was created by the characteristic stretching vibration mode of the Zn–O. The resistivity of the produced films significantly changed with AA concentration in the bath solution. Antibacterial potentials of bare ZnO and ascorbic acid added ZnO films were examined against economically important Staphylococcus aureus (ATCC 25923) gram-positive bacteria and Escherichia coli (ATCC 35218) gram-negative bacterial disease agents via handling paper disc diffusion assay. The obtained diameter of the zones of inhibition was 20.1 mm for E. coli and 28.1 mm for S. aureus at the dose of ZnO+AA 8.0%. These inhibition diameters were larger than the diameter of ampicillin as our positive control alone. This proves that the newly synthesized compound is a powerful antibacterial agent.

Study on organic molecular vibrational dynamics by TR-box-CARS spectroscopy

This paper reported a comparative study of molecular vibrational dynamics in different organic molecules by femtosecond time-resolved folded box-coherent anti-Stokes Raman scattering (TR-box-CARS) spectroscopy. As model system methanol and ethanol molecules are chosen, the coherence transfer between stretching vibration modes of C-H bonds in them are excited and detected at the same time. Different vibration periods and wavenumber spacing are found for the amplitudes of the coherent vibrations of C-H stretch modes in methanol and ethanol molecules. This study makes femtosecond TR-box-CARS possible as a prospective technique for detection and identification of organic molecular species in ambient environments. A simple spatial magic filter and frequency domain filter method with folded TR-box-CARS approach of suppressing the non-resonant FWM background is demonstrated.

An effect of extra compactified dimensions of space in the molecule hbox {NO}_{{2}}

The theory of large extra compactified dimensions of space (ADD-model) predicts that gravity may become strong in a compactification space of the size of a molecule and may affect the vibrational motion of a molecule. In triatomic molecules like hbox {NO}_{{2}} nuclear dynamics is strongly coupled to electronic dynamics at the intersection of electronic states (conical intersection). We discuss experimental results on hbox {NO}_{{2}} which reveal that the collision-free molecule optically excited into a symmetric stretch vibration mode of an electronic state with conical intersection undergoes an irreversible non-radiative transition into an asymmetric stretch vibration mode in combination with a change of the electronic state. We suggest ascribing this irreversible non-radiative transition to a gravitational perturbation on the vibrational motion in hbox {NO}_{{2}}. This gravitational perturbation deactivates the upper state of the optical transition. The width of the absorption line is given by the characteristic time of the gravitational perturbation and not by the radiative lifetime of the excited molecular state.Graphical abstract

Determination of temperature-dependent Fermi resonance in acetonitrile-water binary solution by two-dimensional correlation Raman spectroscopy.

Acetonitrile (AN), as an organic solvent, has a wide range of applications. The C≡N stretching vibration mode (ν2) and the combination mode (ν3 + ν4) are coupled by Fermi resonance (FR). In this work, the phase transition and the interaction mechanism of the 60% AN-water binary solution (AN-Water) were analyzed by calculating FR parameters and two-dimensional correlation Raman spectroscopy (2DCRS). The change in the ν2 band and the base bands ν3 and ν4 caused energy transfer by anharmonic interaction, which led to a change in FR parameters. With a reduced temperature, the energy transfer was caused by microheterogeneity and the energy transfer effect (293-273K), the phase separation (263-233K), and the phase transition of AN (223-173K). The 2DCRS and Gaussian deconvolution provided more information on FR, which revealed the interaction mechanism of the Fermi doublet. The polarity and binding modes of molecules provided a new perspective for analyzing the transmission of electrons and ions in the electrolyte at different temperatures.

Persistent luminescence induced by the introduction of multi-valent Mn ions in K2LiBF6 (B = Al, Ga and In) fluoride phosphors

Mn4+ – activated elpasolite fluorides K2LiBF6 (B = Al, Ga and In) are well-known red-emitting phosphors for white light emitting diodes (WLEDs) application. Such fluorides exhibit narrow emissions at around 630 nm under near ultraviolet (NUV) or blue excitations, but in this work, we introduced an unusually broad emission band in the green to orange region under NUV excitation at low temperature by introducing impurity to the elpasolite structure. The nature of this photoluminescence (PL) has been verified to be from Mn2+ species, so we observed the multi-valence of Mn ions (Mn2+ and Mn4+) in fluorides, which is rarely discussed in literatures. Besides, the influence of Mn2+ on Mn4+ was studied in samples with different Mn4+/Mn2+ ratios. The configuration-coordinate model and crystal theory were employed to help us to get a deeper understanding that the presence of Mn2+ affects the stretching vibration mode ν2 of Mn4+ in octahedra. Furthermore, the thermal quenching of Mn2+ and Mn4+ was studied for ratiometric optical thermometer application. In addition, persistent luminescence (PersL) was found in the proposed fluorides. For example, Under NUV irradiation, white PL was achieved in K2LiGaF6: Mn, and the emission turned to the green once excitation ceased. We herein demonstrated a novel multi-valence synthetic method for dual-color emitting elpasolite fluorides and propose a mechanism for the observation of white PL and green PersL based on the multi-valence properties.

Synthesis, Growth, Structural and Physicochemical Properties of a Novel Linear and Nonlinear UV-Optical Single-Crystal for Photonic Applications: [Ba(C14H20O5)2.Co(SCN)4

The hybrid nonlinear optical crystal of barium (II)-dibenzo-15-crown-5-ether-cobalt (II)-tetra-thiocyanate (BDBCCTC) single crystal with a dimension of 15 × 5 × 3 mm3 was grown by the slow evaporation solution growth technique. The title compound of BDBCCTC belongs to a monoclinic system with a space group of P21/n. The calculated lattice parameters are a = 12.05 (19) Å, b = 20.20 (3) Å, c = 17.36 (3) Å, α = γ = 90˚, β = 101˚, Z = 4 and volume V = 4150 Å3 which are calculated by single-crystal X-ray diffraction and further confirmed by powder X-ray diffraction analysis. The surface morphology and presence of the elements have been identified by FE-SEM and EDAX studies. Additionally, the reverse growth rate of the grown single-crystal was absorbed by etch pits patterns. The C-N stretching vibration modes and other functional groups were identified by FT-IR which are further verified by micro-Raman spectral analysis. The optical bandgap was found to be 3.24 eV by Tauc’s relation. Furthermore, the estimation of solid-state parameters, such as valence electron (Ev = 283), plasma energy ( = 19.384 eV), Penn gap energy ( = 1.823 eV) and Fermi energy (E f = 15.199 eV), have been calculated by standard empirical relation. The thermal stability of the grown BDBCCTC was found to be 352 °C. Moreover, Vickers’s hardness measurement reveals that the grown BDBCCTC compound can be categorized into hard material with n = 0.825. The third-order nonlinear optical properties, such as nonlinear refractive index (), nonlinear absorption coefficient, and third-order nonlinear susceptibility were also determined grown BDBCCTC single crystal exhibits high thermal stability, and moderate by linear transmittance which turn into be a potential candidate for NLO applications such as short pulse generators, pulse shaping, power spreading, and optical limiter.

A new biocompatible phosphate free mesoporous calcium borosilicate glass-ceramics for medical application

Boron plays an important role in life processes such as bone growth and maintenance. Structural and bioactivity properties of phosphate free novel composition of calcium borosilicate mesoporous glass–ceramic is reported. X-ray diffraction studies indicate the amorphous nature of sample and Fourier transmission infrared spectroscopy reveal the possible bending and stretching vibration modes of silicate and borate groups. N2 adsorption–desorption studies reveal the mesoporous structure with average pore diameter of 28 nm and surface area of 101 m2 g−1. The sample exhibits good bone-like hydroxyapatite layer formation after soaking in stimulated body fluids. Biocompatibility test of sample carried out by using myoblasts cell derived from muscle of mouse indicates an excellent biocompatibility.

Isotope effect on the thermal expansion coefficient of atomically thin boron nitride

Atomically thin monoisotopic hexagonal boron nitride (BN) which is electrically insulating and has a high thermal conductivity could be utilized as fillers in electronic packaging materials for thermal dissipation in integrated and miniaturized modern devices. Thermal expansion mismatch in electronic packaging could cause strain and ultimately device failure, so it is valuable to measure and understand the thermal expansion coefficient (TEC) of atomically thin isotopically pure BN. In this work, we studied the TECs of mono-, bi-, and tri-layer isotope-purified BN using Raman spectroscopy and density functional theory calculations including van der Waals dispersion forces. Monolayer (1L) 10BN had a slightly larger experimental TEC than 1L 11BN at close to room temperature: (−5.1 ± 0.8) × 10−6 K−1 and (−4.6 ± 0.8) × 10−6 K−1, respectively. The negative TECs up to 700 K were attributed to the competition between the in-plane stretching vibration modes and out-of-plane bending modes in BN; the lighter isotope leads to a larger absolute TEC due to higher amplitude of its out-of-plane bending modes. The absolute TECs of isotopic BN decreased with increased atomic thickness, which indicates strengthening of the out-of-plane bending rigidity. The deep understanding of the isotope effect on the TEC of two-dimensional (2D) materials also opens a promising pathway to minimize TEC mismatch in 2D van der Waals heterostructures.

Fine structures and their impacts on the characteristic Raman spectra of molten binary alkali tungstates

AbstractComparing with the crystalline tungstate compounds, little work has been carried out and reported on the relation among the microstructure, W–O bond lengths, and characteristic Raman‐active vibration wavenumber of the molten tungstates, which allows us to diagnose and determine the structure of unknown clusters existing in and further predict the physicochemical properties of molten binary alkali tungstates. Raman spectra of an ensemble of eight model clusters were simulated in the present work by density functional theory (DFT) to establish the effect of the fine structures and W–Onb (non‐bridging oxygen) bond lengths of W–O complexes on the characteristic wavenumber of W–Onb Raman‐active vibration modes of the molten tungstates. Results show that the characteristic wavenumbers of the symmetric stretching vibration modes of W–Onb bonds increase almost linearly with the decreasing bond length. The characteristic wavenumbers of W–Onb symmetric stretching vibration modes generally follow [WO4]2− > [WO5]4− > [WO6]6− present in the melt simultaneously. The characteristic wavenumbers were also found to increase with the number of bridging oxygen for the same W–O complex. In situ Raman spectra of molten A2WnO3n + 1 (A = Li, Na, K; n = 1, 2, 3) were then measured in order to verify the correlation observed among the microstructure, W–O bond lengths, and characteristic Raman‐active vibration mode wavenumbers. The correlation was successfully applied to deconvolute the in situ Raman spectrum of the molten Na2W3O10.

Raman study of hydrogen-saturated silica glass

The Raman spectra of saturated solid solutions of hydrogen and deuterium in silica glass, SiO2-0.6H2 and SiO2-0.63D2, have been measured for the first time at liquid nitrogen temperature. The comparative analysis of H2 phonon modes in solid solution of hydrogen in silica glass and those of hydrogen gas shows a decrease in the frequency of rotational modes contrary to an increase in the H–H stretching vibration mode frequency. Hydrogen rotational modes, overlapped with the phonon modes of silica glass, strengthen at an elevated temperature, while the phonon modes of silica glass soften. The isotopic substitution of hydrogen by deuterium leads to a decrease in the stretching vibration mode frequency proportionally to the square root of D2/H2 mass ratio, whereas rotational mode frequencies decrease as a ratio of D2 to H2 inertia moments. The intensity of H2 phonon modes gradually decreases upon the heating of hydrogen-saturated silica glass along with the evolving of dissolved hydrogen.

Industrial dye removal using bio-synthesized Ag-doped ZnO nanoparticles

This contribution reports on the bioremediation of the industrial textile effluent by the valorization of agro-waste extracts of Rosmarinus officinalis (rosemary) leaves using biosynthesized Ag-doped ZnO nanoparticles (NPs), as photocatalysts. Characterization of the NPs was carried out using field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), UV-Visible, photoluminescence (PL), and efficacy in the photocatalytic degradation of dyes in non-synthetic industrial textile effluent. FESEM and XRD results depicted the hexagonal structure of the Ag-doped ZnO NPs with the average particle size of 21.65 ± 0.25 nm for FESEM, in the range of 7.450-38.611 nm from Scherrer equation and 28.946 ± 0.002 nm from the Williamson-Hall plot for XRD. EDS indicated Ag (3.94%), Zn (41.01%), and O (30.52%) atoms in the sample, and the carbon (24.53%) attributed to the phenolic compounds in the plant extract, while ATR-FTIR identified stretching vibration mode of Ag-O and Zn-O at 476 cm−1 and 840 cm−1, respectively. From UV-Vis-NIR, the energy bandgap has amounted to 3.23eV and the photoluminescence emission spectrum indicated the existence of surface defects and oxygen vacancies. Synthesized NPs were used for the treatment of the industrial textile effluent (TE) by assessing the pH and temperature, total suspended solids (TSS), biochemical oxygen demand after 5 days (BOD), chemical oxygen demand (COD). The mineralization thus decontamination of the TE has been confirmed with 63 % degradation of the dye being observed after 100 min visible light exposure. The analyses reported herein indicated that this plant extract synthesized nanoparticles can play an important role in the bioremediation of textile industry wastewater.

Synthesis and electrochemical characterization of pseudocapacitive α-MoO3 thin film as transparent electrode material in optoelectronic and energy storage devices

Molybdenum oxide thin film was deposited on indium tin oxide (ITO) coated glass via a simple and cost-effective approach. Some surface and electrochemical properties of the film were studied. Characteristic peaks from x-ray diffraction patterns indicated a well crystalline orthorhombic structure of MoO3 thin film. Raman spectroscopy revealed Mo–O band bending in the range of wave number below 600 cm−1 and stretching vibration modes in the higher range. Optical characterization showed that the film exhibited strong absorption in the ultraviolet (UV) and high optical transparency across visible light regions. Energy band gap was estimated between 3.36 and 3.44 eV while Urbach energy lied between 0.42 and 0.93 eV. Electrochemical performance of the film was investigated by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS). The results showed that the film yielded relatively high specific capacitance of 220 F g−1 and areal capacity of 4.94 mA h cm−2. In addition, access to more active sites with minimum ion diffusion length of the MoO3 electrode enhanced the redox behavior leading to superior rate capability and excellent long-term cycle stability on the substrate. This study presents a cost effective means of preparing nanoporous MoO3 thin film from chemical reagents. It reveals charge transport capability of MoO3 structure for optoelectronic and energy storage devices.

Reinterpreting the vibrational structure in the electronic spectrum of the propargyl cation (H2C3H+) using an efficient and accurate quantum model.

The B̃1A1 ← X̃1A1 absorption spectra of propargyl cations H2C3H+ and D2C3D+ were simulated by an efficient two-dimensional (2D) quantum model, which includes the C-C stretch (v5) and the C≡C stretch (v3) vibrational modes. The choice of two modes was based on a scheme that can identify the active modes quantitively by examining the normal coordinate displacements (∆Q) directly based on the ab initio equilibrium geometries and frequencies of the X̃1A1 and B̃1A1 states of H2C3H+. The spectrum calculated by the 2D model was found to be very close to those calculated by all the higher three-dimensional (3D) quantum models (including v5, v3, and another one in 12 modes of H2C3H+), which validates the 2D model. The calculated B̃1A1 ← X̃1A1 absorption spectra of both H2C3H+ and D2C3D+ are in fairly good agreement with experimental results.

Concentration and pressure scaling of CH2O electronic-resonance-enhanced coherent anti-Stokes Raman scattering signals.

Nanosecond electronic-resonance-enhanced coherent anti-Stokes Raman scattering (ERE-CARS) is evaluated for the measurement of formaldehyde (CH2O) concentrations in reacting and nonreacting conditions. The three-color scheme utilizes a 532 nm pump beam and a scanned Stokes beam near 624 nm for Raman excitation of the C-H symmetric stretch (ν1) vibrational mode; further, a 342 nm resonant probe is tuned to produce the outgoing CARS signal via the 101403 vibronic transition between the ground (X~1A1) and first excited (A~1A2) electronic states. This allows detection of CH2O at concentrations as low as 9×1014molecules/cm3 (55 parts per million) in a calibration cell with CH2O and N2 at 1 bar and 450 K with 3% uncertainty. The measurements show a quadratic dependence of the signal with CH2O number density. Pressure scaling experiments up to 11 bar in the calibration cell show an increase in signal up to 8 bar. We study pressure dependence up to 11 bar and further apply the technique to characterize the CH2O concentration in an atmospheric premixed dimethyl ether/air McKenna burner flame, with a maximum concentration uncertainty of 11%. This approach demonstrates the feasibility for spatially resolved measurements of minor species such as CH2O in reactive environments and shows promise for application in high-pressure combustors.

Effect of magnesium on the XPS and Raman spectra of (Ba0.5Sr0.5)(Al0.2-xMgxFe0.8)O3-ξ (x ≤ 0.2)

ABSTRACT The perovskite-type cubic oxides have found useful applications in catalysis, solid oxide fuel cells, gas sensors, and membrane technology. XPS and Raman studies of a recently developed (Ba0.5Sr0.5)(Al0.2-xMgxFe0.8)O3-ξ (x = 0–0.2) oxygen-permeable system are reported here. The effect of magnesium is shown to alter the relative amounts of Fe3+, Fe4+, and oxygen species via Fe (2p3/2 and 2p1/2) and O 1s signals. Besides, it causes a surge in oxygen vacancies, an increase in Fe3+ ions, a decline in B – O bond strength (B = Al/Mg/Fe), and a rise in anion flow. The O1s signals at ~ 528.5 and ~531.0 eV correspond to surface oxide and adsorbed (O2 2−, O2−, or O−) species, respectively. Raman spectra offer evidence for symmetric A1g stretching, oxygen vacancies, distorted BO6 octahedra, A-O stretching vibration modes (A = Ba, Sr), and bending B-O linkages. A good correlation is advanced between the XPS and Raman results, in conformity with lattice expansion, Mossbauer data, improved oxygen permeability, enhanced electrical conductivity, and high structural stability realized by means of partial replacement of Al3+ with Mg2+ in (Ba0.5Sr0.5)(Al0.2Fe0.8)O3-ξ earlier.

Structural and optical study of high concentrate Co-doped ZnO nanostructures

High concentrate Co doped ZnO nanostructures, were prepared using solution method. Prepared samples were characterized by different characterization techniques. Structural analysis was done by X ray-diffraction (XRD) and found the formation of the wurtzite hexagonal structure of ZnO without any essence presence of the Co related clusters. Field emission scanning electron microscope (FESEM) images indicated change in surface morphology of ZnO due to introducing of Co ions into ZnO lattice. UV visible spectroscopy showed red shift in the optical band gap of ZnO because of Co doping. Fourier transform infrared spectroscopy (FTIR) showed stretching vibration mode of Zn-O at 527 cm-1which indicated the formation of the wurtzite hexagonal structure of ZnO.

Three stages of hydrogen bonding network in DMF-water binary solution

Three stages of hydrogen bonding (HB) network in N, N-dimethylformamide (DMF)-water binary solution were investigated by Raman spectroscopy with different mixing ratios at room temperature and atmospheric pressure. The results show that the addition of DMF strengthens the HB network of water when the volume fraction of DMF (VDMF) is less than 0.4. However, the tetrahedral structure of water is destroyed when VDMF reaches 0.4, and water molecules and DMF molecules form two DMF-water complexes, namely DMF·3H2O and DMF·2H2O. While VDMF reaches 0.8, the DMF-water complex is transformed into DMF·H2O structure due to the instability of DMF·nH2O (n = 2, 3). In addition, the newly formed HB C=O···H-C, rather than the weak HB C-H···O, leads to the red shift of C–H stretching vibration mode.

Micro-Raman Spectroscopy Assessment of Chemical Compounds of Mantle Clinopyroxenes

The composition of clinopyroxenes is indicative for chemical and physical properties of mantle substrates. In this study, we present the results of Raman spectroscopy examination of clinopyroxene inclusions in natural diamonds (n = 51) and clinopyroxenes from mantle xenoliths of peridotites and eclogites from kimberlites (n = 28). The chemical composition of studied clinopyroxenes shows wide variations indicating their origin in different mantle lithologies. All clinopyroxenes have intense Raman modes corresponding to metal-oxygen translation (~300–500 cm−1), stretching vibrations of bridging O-Si-Obr (ν11~670 cm−1), and nonbridging atoms O-Si-Onbr (ν16~1000 cm−1). The peak position of the stretching vibration mode (ν11) for the studied clinopyroxenes varies in a wide range (23 cm−1) and generally correlates with their chemical composition and reflects the diopside-jadeite heterovalent isomorphism. These correlations may be used for rough estimation of these compounds using the non-destructive Raman spectroscopy technique.