Space Group Pnma Research Articles

Enhancement of the magnetocaloric effect in Nd0.6-xGdxSr0.4MnO3 (0.02 ≤ x ≤ 0.1) perovskite manganites: the role of Gd3+ ionic substitution

The influence of Gd3+ doping on the magnetocaloric properties of Nd0.6-xGdxSr0.4MnO3 (0.02 ≤ x ≤ 0.1) compounds, prepared using auto-combustion sol-gel technique, has been studied . Rietveld refinement of the X-ray diffraction (XRD) data has shown all compounds to be nanocrystalline with single-phased orthorhombic structures that index to the Pnma space group. The unit cell volumes reduce as the Gd3+ ions gradually substitute the Nd3+ones. The tuning Mn4+/Mn3+ ratio for all compounds, which are slightly lower than that of the Gd-free compound, demonstrates almost equal amounts of both ions. A ferromagnetic-to-paramagnetic transition is observed with rising temperature wherein the Curie temperature (TC) gradually drops with increasing Gd3+ concentration (x). All materials exhibit ferromagnetism at 2 K, with saturation magnetization values that increase slightly with x. Both the calculated maximum magnetic entropies () and relative cooling powers (RCP) increase to relatively large values with increasing temperature and x values. The values obtained for and RCP for Nd0.6-xGdxSr0.4MnO3 (0.02 ≤ x ≤ 0.1) are comparable with those of standard pure Gd revealing their potential as magnetic refrigeration systems.

Study of Structural, Thermal and Electrical Properties of Sr-Doped CaMnO<sub>3</sub>

Sr-doped CaMnO3 materials have wide applications due to their thermal and electrical properties. The importance of the synthesis of Sr-doped CaMnO3 material for various applications encourages researchers to evaluate and refine the synthesis process. In this study, Ca1-xSrxMnO3 (x = 0; 0.05; 0.1; 0.15; 0.2) system has been prepared by sol-gel method followed by conventional sintering process at 850°C for 8 hr. A thorough discussion has been made on the outcomes derived from the investigation on the structural, electrical, and thermal properties of Sr-doped CaMnO3 system using powder x-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, DC fourprobe method, thermal expansion studies, and thermoelectric power analyses. The XRD patterns of all prepared samples exhibited single phase with orthorhombic crystal structure (space group Pnma). Rietveld refinements were performed for all the patterns by using Fullprof software to extract the structural properties. The values of unit cell volume of samples tend to increase with the increment of dopant concentration, whereas the crystallite size values were decreased with dopant concentration. The microstructures of all the samples were studied using SEM, and elemental compositions were confirmed from the EDS results. Linear thermal expansion coefficients of all the samples were found to have moderate values in the temperature range from 30°C to 800°C. The electrical properties of all the system of samples were studied in the temperature range from 30°C to 400°C using DC fourprobe conductivity setup. It was found that all the samples exhibited semiconductor nature. Sr-content on the A-site suppress the electrical resistivity up to 10% of concentration and 5% dopant content exhibited the lowest electrical resistivity. The values of Seebeck coefficient found to vary from -160 µV/K to -124 µV/K with the increase of dopant content in the parent compound.

Evidence of Spin Reorientation from Γ4 to Γ2 and Sign Reversal Exchange Bias in CeCrO3 Nanoparticles

Herein, the temperature‐dependent magnetic structure and sign reversal exchange bias in CeCrO3 using magnetization data and time‐of‐flight neutron diffraction data which is given less attention among RCrO3 are investigated. While nuclear structural analysis using Rietveld refinement exhibits distorted orthorhombic structure within Pnma space group, temperature dependence of the magnetic structure using neutron diffraction reveals possible spin configurations, namely, Γ4, Γ2, and Γ1, within the temperature range of 6–300 K. Temperature‐dependent magnetization shows compensation temperature, Tcomp, at 58 K, spin reorientation temperature, TSR, at 15 K along with a Neel temperature, TN, at 260 K which is the outcome of the competition between canted antiferromagnetic ordering of Cr3+ ions and Ce3+ ions in CeCrO3. Furthermore, the magnetization versus magnetic field (M vs H) measurements indicate transition of the Γ4 spin structure to Γ2 spin structure around TSR which is further supported by reversible‐to‐irreversible changes observed in temperature‐dependent MFCC and MFCW. Moreover, a temperature‐driven sign reversal of exchange bias in CeCrO3 is observed, resulting from the competition between antiferromagnetic coupling between chromium moment (MCr) and cerium moment (MCe) in these nanoparticles. This intriguing behavior holds significant potential for the development of thermally assisted magnetic random access memory.

Influence of La3+ doping on structural and optical properties of SrCeO3 perovskite

The SrCe1-xLaxO3 (x = 0.0, 0.02, 0.4, 0.6, and 0.10) perovskite materials have been successfully synthesized by auto-combustion method and calcined at 1100°C. The XRD patterns reveal a highly crystalline orthorhombic crystal structure with a Pnma space group in all samples. The TEM micrograph shows a spherical morphology of the 10 mol% La3+ doped SrCeO3 perovskite sample alongwith the SAED pattern confirming its highly crystalline nature. The incorporation of La3+ ion in the SrCeO3 perovskite has been confirmed by the Raman and Fourier transform infrared (FTIR) measurements. The UV–vis absorption spectra at room temperature show various bands, with a strong absorption band observed below 400 nm. The optical band gap of the undoped and La3+ doped samples have been calculated and it is smaller for the La3+ doped perovskite samples than that of the undoped perovskite sample. Therefore, the La3+ doped SrCeO3 perovskite may be applicable for optoelectronic applications.

Synthesis and Optical Properties of Organic-Inorganic Hybrid[(18-Crown-6)K][MoOCl4(H2O)

Crown ether anchored organic-inorganic hybrid halides have been recently reported as interesting luminescent materials in the visible region of electromagnetic spectrum. Is it possible to develop such crown ether anchored hybrid materials for near infrared emission? Motivated by this question, we designed a new hybrid material, namely, [(18-Crown-6)K][MoOCl4(H2O)]. 18-Crown-6 ether bound with K+ form the cationic part [(18-Crown-6)K]+. The K+ of [(18-Crown-6)K]+ electrostatically interacts with Cl- of the anionic part [MoOCl4(H2O)]-, forming the hybrid crystal [(18-Crown-6)K][MoOCl4(H2O)]. It crystallizes in orthorhombic crystal system with Pnma space group. The Mo(V) possesses one d-electron (d1) in C4v point group symmetry in the [MoOCl4(H2O)]- polyhedra. This electronic configuration leads to multiple spin-allowed d-d transitions along with a ligand to metal charge transfer (LMCT) resulting into multiple optical absorption bands in the near UV-visible-near infrared (NIR) region. The lowest energyd-dtransition via 2E to2B2 leads to NIR PL with peak at 952 nm, but with a poor intensity at room temperature.

Luminescence Properties of Cs<sub>3</sub>Cu<sub>2</sub>I<sub>5</sub> Phosphors Powder with Solid State Method

The low-temperature solid-state method is utilized to prepare Cs3Cu2I5 phosphors powder by using the cesium iodide (CsI) and cuprous iodide (CuI) as the raw materials. The phase structures of samples were investigated by using X-ray spectrum and steady-state fluorescence spectrometer. The experimental results show that all of samples were crystallized in the orthorhombic structure with pnma space group at the annealing temperature of 100-400°C. Cs3Cu2I5 phosphors exhibits a strong blue photoluminescence emission with peak at 440nm under excitation at 310nm. With the increase of the annealing temperature in the range of 100-400°C, the photoluminescence quantum yield (PLQY) of Cs3Cu2I5 powder achieved the 79.95%. It is revealed that the prepared Cs3Cu2I5 powder phosphors potentially have the promising application in the blue light emitting materials.

Synthesis and Characterization of LaMnO3 Prepared by Hydrothermal Synthesis Method

Abstract LaMnO3 powders were prepared by hydrothermal synthesis method by varying citric acid to metal ions. The ratio of citric acid to metal ions is one of the parameters that have an affect on purity of LaMnO3 prepared by hydrothermal method. It is necessary to control the parameter to obtain the good quality of the final product of LaMnO3. LaMnO3 with variation molar ratio of citric acid to metal ion (CA/M) of 0, 1 and 4 were prepared. To determine the morphology, crystall structure, and phase composition, the powders were characterized by Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) and X-Ray Diffraction (XRD) techniques. The obtained results revealed that the morphology of sample CA/M = 0 has rod-like shape, CA/M = 1 was in the formed of irregular fine particles that stuck together and formed agglomerates, while the spherical morphology with various diameters were formed in the sample CA/M = 4. The XRD analysis demonstrated that sample CA/M = 1 had a single phase while in sample CA/M = 0 and CA/M = 4 others phase were detected such as La (OH)3 and La2O3. There was a change in crystall structure of the LaMnO3 phase in each sample due to the presence of citric acid. The peaks position in sample CA/M = 0, 1, dan 4 exhibit orthorhombic, rhombohendral and cubic structure with space group of Pnma, R -3c and Pm-3m respectively.

Praseodymium induced symmetry switching and electrochemical characteristics of LaCoO3 nanostructures

A comparative study of the crystal structures and electrochemical characteristics of bulk and nanoscale La1-xPrxCoO3 (x = 0, 0.3 and 0.6) perovskites is made using synchrotron x-ray diffraction, cyclic voltammetry, and galvanostatic charge/discharge methods. It is shown that the sol-gel synthesized nano structures and bulk LaCoO3 exhibit different crystal structures, viz., rhombohedral [a = b = 5.4401 Å, c = 13.134 Å (on hexagonal axes), Z = 6, R3‾c] and monoclinic [am = 5.3865 Å, bm = 5.4482 Å, cm = 7.6365 Å, βm = 89.010°, Z = 4, I2/a], respectively. The evidence for CoO6 octahedra distortion in bulk LaCoO3 is also gathered from the three distinct Raman active modes at 518, 646, and 688 cm−1 emerging due to the Jahn-Teller effect, which, in-turn, reduces the crystal symmetry for achieving structure stabilization. This amounts to changes in Co–O bond lengths and Co–O–Co bond angles with promotion of t2g electron to eg level simultaneously for Co3+(3d6) to attain an intermediate spin state (S = 1) or higher. However, Pr-insertion induces phase transition to orthorhombic in both but with space group Pnma in nanostructures and equivalent Pbnm in bulk. The substitution effect on the specific capacitance (C) is opposite in nature, i.e., while ‘C’ decreases from 149 to 12 F/g in nano structures, it increases from 0.4 to 4 F/g in bulk with increase in Pr-content from x=0 to 0.6. A galvanostatic charge-discharge test of pristine nano LaCoO3 performed at a constant scan rate of 50 mVs−1 reveals electrode electrochemical stability by retaining 96 % of specific capacitance ∼82.5 F/g for 2000 cycles at least. The variation in the crystal structure and bond length and/or angle plays a key role in controlling the electrochemical performance of Pr-substituted LaCoO3 perovskites.

Structural, magnetic, and magnetocaloric characterizations of geometrically-frustrated SrRE2O4 (RE = Gd, Dy, Ho, Er) oxides for low-temperature cooling applications

The magnetocaloric (MC) properties of many rare earth (RE)-based magnetic solids have been intensively investigated. This research aims to develop suitable MC materials for low-temperature cooling application and to better elucidate their intrinsic properties. We have fabricated four single-phase SrRE2O4 (RE = Gd, Dy, Ho, Er) oxides and conducted a systematic experimental investigation into their structural, magnetic, and low-temperature MC properties. All these SrRE2O4 oxides crystallize in an orthorhombic structure (space group Pnma) and exhibit typical geometrical frustration. This frustration arises from the one-dimensional RE ion zigzag ladders along the c-axis, which link the two-dimensional honeycomb lattice in the ab plane. The elements in SrRE2O4 oxides are uniformly distributed and present with valence states of Sr2+, RE3+, and O2−, respectively. Large low-temperature MC effects and notable performances are realized in these SrRE2O4 oxides, determined by the MC parameters of magnetic entropy change, refrigerant capacity, and temperature-averaged entropy change (with a lift of 5 K). These MC parameters under a magnetic field change of 0–70 kOe are as follows: 34.18 J/kgK, 275.88 J/kg, and 30.74 J/kgK for SrGd2O4; 18.13 J/kgK, 253.83 J/kg, and 17.54 J/kgK for SrDy2O4; 18.81 J/kgK, 354.77 J/kg, and 18.61 J/kgK for SrHo2O4; and 22.63 J/kgK, 284.25 J/kg, and 21.97 J/kgK for SrEr2O4. These values are comparable to those of most recently updated low-temperature MC materials with remarkable performances, making these SrRE2O4 oxides highly interesting for practical cooling applications.

Weak ferromagnetic interactions of [formula omitted] induced by coupling of the crystal and related lattice vibrations

There is an increase in demand of the next-generation spintronic devices with stable structural and magnetic properties in varying temperatures. An orthoferrites structure of the Pnma space group has been successfully prepared using high temperature solid-state reaction. In the Sm2Fe2O5+δ (SFO) material, Fe3+ ions occupy edge-cantered and face-cantered positions forming the tilted FeO6 octahedrons with Glazer's notation tilt a−a−c+. The ordering of the rare-earth ions at compensation temperature (Tcomp=2.3K), spin-flip transition in the range of 9.4−45.6K, and a second-type spin-reorientation transition around the anisotropy barrier with lower and higher transitional temperatures, TL=465 and TH=480K respectively. The canting of spins along with disordered spins at the surface results in a non-zero Tcomp and unsaturated magnetization. It is inferred that thermal activation of particle's moment over the anisotropy barriers (known as Kneller's law) only occurs above room temperature.

Synthesis and study of structural, electric, and dielectric behavior of La0.5Sm0.2Sr0.3Mn1-xFexO3 perovskite

In this study, the synthesized samples La0.5Sm0.2Sr0.3Mn1-xFexO3 (x = 0.05, 0.15 and 0.20) were thoroughly investigated for their crystalline structure, electrical conductivity, and dielectric properties, the samples were prepared using autocombustion method. According to the X-ray diffraction study, the samples crystallized in an orthorhombic symmetry with the Pnma space group. To measure the dielectric characteristics, impedance spectroscopy was conducted over the temperature range of 100–260 K and a frequency range of 100 Hz to 1 MHz. Measurements of AC conductivity are indeed utilized to investigate the transport properties of materials being studied. The results indicated that both temperature and frequency significantly influence the conduction process. Three theoretical hypotheses were proposed to explain the hopping conduction: overlapping large polaron tunneling (OLPT), the non-overlapping small polaron tunneling (NSPT) mechanism, and correlated barrier hopping (CBH). It is also shown that the conductivity diminishes with an increase in Fe content. La0.5Sm0.2Sr0.3Mn1-xFexO3 (x = 0.05, 0.15 and 0.20) can be used in electronic applications because of the high permittivity values confirmed by the dielectric measurements. With the aim of evaluating the distinct impacts of electrodes, grain boundaries, and grains on the complex impedance results, an appropriate alternative electrical circuit was utilized. Analysis of the sample's modulus indicated non-Debye characteristics and electrical relaxation phenomena. The materials exhibit good electrical properties, as well as strong chemical and thermal stability.

Energy transfer mechanism in infrared-emitting NaYGeO4:Tm3+, Ho3+ phosphors

Two series of NaY0.85Tm0.15-xHoxGeO4 (x = 0.005–0.03) and NaY0.85-xTm0.15HoxGeO4 (x = 0.0–0.055) phosphors have been prepared by the citrate technique. According to XRPD study, all the germanates crystallize in olivine structure and have an orthorhombic lattice, space group Pnma, Z = 4. The diffuse reflectance spectra have been measured and the optical band gap has been estimated. Under 808 nm laser diode excitation, the NaYGeO4:Tm3+, Ho3+ samples exhibit luminescence in the range of 1640–2240 nm, which is caused by 3F4 → 3H6 transition in Tm3+ and 5I7 → 5I8 transition in Ho3+ ions. The highest intensity of holmium lines, while maintaining relatively high intensity of thulium lines, was observed for NaY0.82Tm0.15Ho0.03GeO4, NaY0.815Tm0.15Ho0.035GeO4 samples with the Tm3+/Ho3+ ratio close to 5/1. The luminescence decay kinetics has been studied and the rate of energy transfer from Tm3+ to Ho3+ ions has been calculated. The obtained results indicate an effective energy transfer accelerated by migration due to dipole-dipole interaction. The mechanism of excitation and infrared luminescence in NaYGeO4:Tm3+, Ho3+ phosphors has been proposed.

Spectroscopic, vibrational and structural insights into LaYbO3:Pr3+ and LaLuO3:Pr3+,Tb3+ perovskites at ambient and high-pressure conditions

The interlanthanide perovskites LaYbO3:Pr3+ and LaLuO3:Pr3+,Tb3+ were synthesized by a solid-state reaction and characterized at ambient conditions by means of X-ray diffraction (XRD), Raman spectroscopy and photoluminescence techniques. XRD measurements have shown that the synthesis method provided samples with pure perovskite phase (space group Pnma) for LaYbO3, while in the case of the LaLuO3 compound small traces of Lu2O3 could be found after several annealing. Up to 13 Raman active modes were observed in the Raman spectra of the studied perovskites and theoretical calculations performed for LaYbO3 allowed to assign their symmetry. Regarding their optical properties, the emission from Tb3+ ions at B sites of the ABO3 perovskite could be distinguished. Moreover, NIR emission from Pr3+ was observed in the LaLuO3 perovskite at ∼1000 nm and 1250–1600 nm. Emission in these spectral regions could be relevant for Si-based solar cell applications and fiber optic amplifiers, respectively. Moreover, the stability of both perovskites under high-pressure conditions has been studied spectroscopically, finding that LaYbO3 is stable up to 19 GPa and that LaLuO3 undergoes a possible pressure-induced phase transition at ∼21–24 GPa. This makes LaLuO3 the first interlanthanide perovskite showing phase transition under 40 GPa.

UVB emitting phosphors based on singly and co-doped Ce3+, Gd3+ in Li4ZrF8 phosphors

Preparation of Li4ZrF8:Ce3+ and Li4ZrF8:Ce3+,Gd3+ phosphors is described. Data on luminescence characteristics are presented. Hydrothermal route was employed for the synthesis. Li4ZrF8 crystallizes in orthorhombic system with Pnma space group. Li atoms are distributed over two sites, both having same coordination of six. Zr is also similarly distributed over two 8 coordinated sites. Li4ZrF8:Ce3+ emits a broad band UVB light, while the emission of Li4ZrF8:Ce3+,Gd3+ is in form of a narrow line around 311 nm attributed to 6P7/2 → 8S7/2. Both phosphors exhibited a broad excitation spectrum with a peak at 253 nm. The excitation and emission properties are thus adequate enough to obtain UVB light sources using a conventional high pressure mercury vapour lamp or an ultraviolet LED.

Crystal Structure and Microwave Dielectric Characteristics of Novel Ba(Eu1/5Sm1/5Nd1/5Pr1/5La1/5)2Ti4O12 High-Entropy Ceramic

High-permittivity Ba(Eu1/5Sm1/5Nd1/5Pr1/5La1/5)2Ti4O12 (BESNPLT) high-entropy ceramics (HECs) were synthesized via a solid-state route. The microstructure, sintering behavior, phase structure, vibration modes, and microwave dielectric characteristics of the BESNPLT HECs were thoroughly investigated. The phase structure of the BESNPLT HECs was confirmed to be a single-phase orthorhombic tungsten-bronze-type structure of Pnma space group. Permittivity (εr) was primarily influenced by polarizability and relative density. The quality factor (Q×f) exhibited a significant correlation with packing fraction, whereas the temperature coefficient (TCF) of the BESNPLT HECs closely depended on the tolerance factor and bond valence of B-site. The BESNPLT HECs sintered at 1400 °C, demonstrating high relative density (>97%) and optimum microwave dielectric characteristics with TCF = +38.9 ppm/°C, Q×f = 8069 GHz (@6.1 GHz), and εr = 87.26. This study indicates that high-entropy strategy was an efficient route in modifying the dielectric characteristics of tungsten-bronze-type microwave ceramics.

Green synthesis of calcium nanoferrites using leaf extract of Brassica oleracea for photocatalysis of malachite green dye

The calcium ferrite nanoparticles were made by the sol–gel process. X-ray diffraction, a scanning electron microscope, and UV–vis spectroscopy were used to analyze the material. There is an orthorhombic phase in the space group Pnma. There were four techniques used to calculate the average crystallite size. Using ImageJ software, the particles were aggregated and their size was ascertained. Using energy-dispersive X-ray (EDX) analysis, the composition of the material was ascertained. 2.29 eV was determined to be the band gap. Vibrating test magnetometer (VSM) provided an explanation for the materials’ magnetic property. A decreased band gap energy is responsible for the 90% degradation of malachite green dye at a concentration of 15 mg/L in 150 min, with a four-cycle reusability.

Two Perovskite Modifications of BiFe0.6Mn0.4O3 Prepared by High-Pressure and Post-Synthesis Annealing at Ambient Pressure

BiFeO3-related perovskite-type materials attract a lot of attention from the viewpoint of applications and fundamental science. In this work, we prepared two modifications of heavily Mn-doped BiFeO3 with the composition of BiFe0.6Mn0.4O3. A high-pressure (HP) modification was prepared at about 6 GPa and 1400 K. An ambient pressure (AP) modification was prepared by heating the HP modification at 780 K in the air at AP (post-synthesis annealing). Crystal structures of both modifications and in situ transformation were investigated with synchrotron powder X-ray diffraction. The transformation started at about 700 K and finished at about 780 K. The HP modification crystallized in space group Pnma with a = 5.57956 Å, b = 15.70576 Å, and c = 11.22557 Å, and the AP modification crystallized in space group Pbam with a = 5.63839 Å, b = 11.2710 Å, and c = 7.75923 Å (all parameters were at room temperature). Post-synthesis annealing of the HP modification (conversion polymorphism) is the only way to prepare the Pbam modification of oxygen stoichiometric BiFe0.6Mn0.4O3. Magnetic properties of both modifications have been reported. The Néel temperatures are TN = 350 K (HP) and TN = 335 K (AP). HP modification shows larger spin canting. Both modifications show negative magnetization phenomena at low temperatures in low magnetic fields.

Flux Crystal Growth, Structure, and Optical Properties of LiLa3Ti2S3O6: An Oxysulfide Phase Derived from K2NiF4-Type Structure.

Single crystals of a new titanium oxysulfide, LiLa3Ti2S3O6, were grown from a KI molten salt. Single-crystal X-ray diffraction analysis revealed that LiLa3Ti2S3O6 crystallizes in the space group Pnma with lattice parameters of a = 11.7319(4) Å, b = 3.94787(14) Å, and c = 20.6885(6) Å. In this structure, the one-dimensional chains of corner-sharing TiO5S octahedra are further corner-linked via equatorial and apical oxygen atoms to form unique corrugated two-dimensional perovskite-type layers in the ab plane with one octahedral thickness. These layers were intervened along the c-axis by the LaS rock-salt layers corrugated concomitantly with the perovskite-type layers, and LiO2S2 tetrahedral chains were located between these two types of two-dimensional layers. LiLa3Ti2S3O6 can be viewed as a modified K2NiF4-type structure with TiO5S octahedral layers stacked in a zigzag manner along the c axis. The oxysulfide has a direct-type band gap of 1.85 eV, based on UV-vis-NIR diffuse reflectance measurements. First-principles calculations showed that the conduction band minimum mainly consists of Ti 3d orbitals, and the valence band maximum consists of S 3p, O 2p, and Li 2s orbitals. The electronic structures near the Fermi level are similar to those of the structurally related photocatalytic oxysulfides Y2Ti2S2O5 and La5Ti2CuS5O7.

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Observation of the multiple magnetic phases in double perovskite Pr1.8La0.2CoFeO6

The structural and magnetic properties of the double perovskite Pr1.8La0.2CoFeO6 have been investigated. The X-ray diffraction study shows that the system acquires room-temperature orthorhombic phase with the Pnma space group. The X-ray photoemission spectroscopy (XPS) measurement confirmed that the B-site ions are present in mixed valence states i.e. Co has been found in Co2+ and Co3+ valance states whereas Fe has been found in Fe3+/Fe4+. Magnetic measurements of the system confirm the existence of several fascinating magnetic behaviors, such as long-range canted antiferromagnetism withTN ∼ 271 K, giant exchange bias, and re-entrant cluster glass phase (TG ∼ 33 K). Field-dependent magnetization shows a large spontaneous exchange bias; HSEB∼ 1.8 kOe and giant conventional exchange bias, HCEB∼ 2.4 kOe at 5 K. Antiferromagnetic materials with large exchange bias can be utilized in high-density spintronic devices. Temperature-dependent Raman study demonstrates that the observed phonon mode exhibits anomalous behavior close to the magnetic transition temperature. Analysis of anomalous softening of phonon mode below TN, clarifies the presence of significant spin-phonon coupling while the magnetostriction effect does not play any significant role in the observed phonon anomaly.