L-histidine Hydrochloride Monohydrate Research Articles

Effect of L-histidine hydrochloride monohydrate (LHICL) doping in potassium dihydrogen phosphate (KDP) on single crystal growth, structural, optical, electrical, and mechanical traits

Effect of L-histidine hydrochloride monohydrate (LHICL) doping in potassium dihydrogen phosphate (KDP) on single crystal growth, structural, optical, electrical, and mechanical traits

Magic angle spinning effects on longitudinal NMR relaxation: 15N in L-histidine

Solid-state magnetic resonance is a unique technique that can reveal the dynamics of complex biological systems with atomic resolution. Longitudinal relaxation is a mechanism that returns longitudinal nuclear magnetization to its thermal equilibrium by incoherent processes. The measured longitudinal relaxation rate constant however represents the combination of both incoherent and coherent contributions to the change of nuclear magnetization. This work demonstrates the effect of magic angle spinning rate on the longitudinal relaxation rate constant in two model compounds: L-histidine hydrochloride monohydrate and glycine serving as proxies for isotopically-enriched biological materials. Most notably, it is demonstrated that the longitudinal N15 relaxation of the two nitrogen nuclei in the imidazole ring in histidine is reduced by almost three orders of magnitude at the condition of rotational resonance with the amine, while the amine relaxation rate constant is increased at these conditions. The observed phenomenon may have radical implications for the solid-state magnetic resonance in biophysics and materials, especially in the proper measurement of dynamics and as a selective serial transfer step in dynamic nuclear polarization.

Shock wave induced order to disorder type phase transition of cobalt chloride hexahydrate doped l-histidine hydrochloride monohydrate single crystal

The impact of supersonic shock waves upon materials is one of the fascinating areas of active research in material science. Phase transition behaviour of materials, when subjected to shock waves, is also of great interest in this field. In the present investigation, we have proved the impact of shock wave-induced order–disorder type phase transition of cobalt chloride hexahydrate doped L-histidine hydrochloride monohydrate single crystal. The test crystal was subjected to the corresponding shock pulse counts of 0, 1, 2, 3, and 4 with Mach number 1.7 until the third shock condition, there wasn't a phase change; however, in the fourth shocked condition, there was a phase transition of the order–disorder type noted. X-ray diffractometry, Raman spectroscopy, and UV–Visible spectroscopy are three different analytical techniques that have been used to confirm the aforementioned phase transitions. The order–disorder phase transition enables the investigation of novel aspects of a material's structural properties. The grown crystal had reacted to shock wave exposure in terms of the type of phase transition order–disorder.

Investigations on structural and optical properties of L-histidine hydrochloride monohydrate crystals at dynamic shock wave-loaded conditions

Investigations on structural and optical properties of L-histidine hydrochloride monohydrate crystals at dynamic shock wave-loaded conditions

Growth and Characterization of Single Crystals of l-Histidine Hydrochloride Monohydrate for Nonlinear Optical Applications

In the present study, we have focused on the growth of semi-organic single crystals, as they play a vital role in the generation of a terahertz pulse and its potential applications. The single crystals of l-histidine hydrochloride monohydrate (LMHCL) were grown by slow evaporation solution growth by using deionized water as a solvent in a controlled atmosphere. Good quality crystals of the required size were obtained within 2 weeks. To estimate the lattice dimensions and get the structural information, powder x-ray diffraction (PXRD) study was performed in which we have found that the crystal belongs to the orthorhombic crystal system with space group P212121. The functional groups and the corresponding vibrational mode were confirmed using Fourier transform infrared (FTIR) and Raman spectroscopy, respectively. To study the optical properties UV–Vis transmission spectrum and photoluminescence (PL) were recorded. It was observed that the single crystal has a high value of transmission over a long range of wavelength which signifies that the crystal is a good candidate for nonlinear optical (NLO) applications. The UV cut-off wavelength is found to be 236 nm. The grown single crystals were studied by time-domain terahertz spectroscopy (THz-TDS) for photonic applications and the refractive indices were calculated and it is found that the refractive index is nearly equal to 3.4.

Exploring Accuracy Limits of Predictions of the 1H NMR Chemical Shielding Anisotropy in the Solid State.

The 1H chemical shielding anisotropy (CSA) is an NMR parameter that is exquisitely sensitive to the local environment of protons in crystalline systems, but it is difficult to obtain it experimentally due to the need to concomitantly suppress other anisotropic interactions in the solid-state NMR (SSNMR) pulse sequences. The SSNMR measurements of the 1H CSA are particularly challenging if the fast magic-angle-spinning (MAS) is applied. It is thus important to confront the results of both the single-crystal (SC) and fast-MAS experiments with their theoretical counterparts. Here the plane-waves (PW) DFT calculations have been carried out using two functionals in order to precisely characterize the structures and the 1H NMR chemical shielding tensors (CSTs) of the solid forms of maleic, malonic, and citric acids, and of L-histidine hydrochloride monohydrate. The level of agreement between the PW DFT and either SC or fast-MAS SSNMR 1H CSA data has been critically compared. It has been found that for the eigenvalues of the 1H CSTs provided by the fast-MAS measurements, an accuracy limit of current PW DFT predictions is about two ppm in terms of the standard deviation of the linear regression model, and sources of this error have been thoroughly discussed.

Growth, characterization, NLO and biological activities of Fe(III) ions doped Mn(II) L-Histidine hydrochloride monohydrate crystals

Powder XRD, EPR, optical,NLO activity and Biological activities of Fe(III)doped Mn(II)L-Histidine Hydrochloride Monohydrate (LHICl) was carried out at room temperature to ascertain the structural properties. In EPR, the angular variation of Fe(III) hyperfine lines indicated a single site, with spin Hamiltonian parameters (g) values g = 2.0292, The calculated results of the Fe(III)doped Mn(II)L-substitutes the Fe(III) ion in the host lattice, and it has orthorhombic symmetry. The EPR evaluated lattice cell parameters, a = 1.5320, b = 0.8450 and c = 0.6834 nm and V = 884.69 Å3 and optical absorption data Dq = 700, B= 610, C= 2360 [α] = 90 cm-1 were corroborated to obtain various bonding parameters, from which the nature of bonding in the complex was discussed. FT-IR and powder XRD studies were used to observe the effect of dopant on structural parameters of the host lattice.

Terahertz time-domain spectroscopy of l-histidine hydrochloride monohydrate

The low-frequency absorption spectrum of l-histidine hydrochloride monohydrate (LHHM) over 0.5–4.0 THz was measured by terahertz time-domain spectroscopy (THz-TDS). The comparison between the THz absorption spectra of LHHM and l-histidine (LHis) was made. The two distinctive THz spectra of LHHM and LHis indicate that THz spectroscopy is sensitive to different specimens. The low-temperature THz spectral features of LHHM presented the blue-shift and splitting as the temperature decreased. Solid-state density functional theory (DFT) calculation of the vibrational modes of LHHM was performed for better understanding the THz characteristic spectrum, and the validity of the calculation modes was confirmed by comparing with the experimental observations. Powder X-ray diffraction (PXRD) was also carried out to check the structures of LHHM and LHis.

Unique optical properties of Eu3 + doped l-histidine hydrochloride mono hydrate single crystals from low temperature growth technique

A low-temperature solution method was utilized to grow single crystals of Eu3+doped l-histidine hydrochloride monohydrate. The quality of the crystals was confirmed by high-resolution X-ray diffraction measurements with full width at half maximum (FWHM) of rocking curve at 8arc per sec. The incorporation of Eu3+ ions into the lattice was confirmed by functional group analysis using Fourier Transform Infrared (FTIR) spectroscopy. The amount of Eu3+ ions was found to be 0.08 weight (%) using energy dispersive X-ray analysis. The crystal's thermal and mechanical properties were tested as well. The unique spectral properties such as UV–Vis transmittance, nonlinear optical efficiency (NLO), photoluminescence (PL) and its lifetime were measured. The PL study revealed that the intensity of 5D0→7F2 emission of Eu3+ is stronger than that of 5D0→7F1 emission and the decay measurement showed a life time of 7.2410μs. The photoluminescence results prove that l-histidine hydrochloride monohydrate is a new, highly efficient host material for europium ion red emissions.

Investigations on structural and photoluminescence mechanism of cerium doped l-Histidine hydrochloride mono hydrate single crystals for optical applications

Semi organic nonlinear optical material of Ce3+ ion added l-Histidine hydrochloride monohydrate (LHHC) crystals have been grown successfully by the slow evaporation solution technique (SEST) as well as Sankaranarayanan-Ramasamy (SR) technique. Unit cell data have been measured from the single crystal X-ray diffraction analysis and High resolution X-ray diffraction analysis (HRXRD) study shows relatively a good crystalline perfection. Fourier transform infra-red spectroscopy (FTIR) spectra indicates that the Ce3+ ion is coordinated with carboxylate group of grown crystal. The lower UV-cutoff wavelength of the incorporation of Ce3+ ion in LHHC is 240 nm. The incorporation of Ce3+ ion in the crystal lattice was observed by energy dispersive X-ray analysis (EDAX). The nonlinear optical (NLO) efficiency of SR-grown crystal is 3.7 times greater with respect to potassium dihydrogen phosphate (KDP). We report first-time the photoluminescence (PL) mechanism of emission spectrum, which shows broad band located at 350 nm corresponding to 5d → 4f transition of Ce3+ ion and excited by 250 nm wavelength. The excitation spectrum shows a band at 258 nm due to the 4f → 5d transition of Ce3+ ion. The nature of decay curve of the grown crystal is bi-exponential with a long life time of τ2 is 8.8270 μs.

Optical investigations on Tb3+ doped l-Histidine hydrochloride mono hydrate single crystals grown by low temperature solution techniques

The potential nonlinear optical material of Terbium (Tb3+) ion doped l-Histidine hydrochloride monohydrate (LHHC) single crystals were successfully grown. Tb3+:LHHC crystals of 7mm×5mm×3mm and 59mm length and 15mm diameter have been grown by the slow solvent evaporation and Sankaranarayanan-Ramasamy (SR) techniques respectively. The grown crystals were characterized by single crystal X-ray diffraction analysis to confirm the crystalline structure and morphology. High resolution X-ray diffraction (HRXRD) studies revealed that the SR grown sample shows relatively good crystalline nature with 9″ full-width at half-maximum (FWHM) for the diffraction curve. Functional groups were identified by Fourier transform infra-red spectroscopy (FTIR). The optical transparency and band gaps of grown crystals were measured by UV–Vis spectroscopy. Thermogravimetric and differential thermal analysis (TG/DTA) studies reveal that the crystal was thermally stable up to 155°C in SR grown crystal. Surface morphology of the growth plane was observed using scanning electron microscopy (SEM). The incorporation of Tb ion was estimated by EDAX. The frequency-dependent dielectric properties of the crystals were carried out for different temperatures. Vickers hardness study carried out on (100) face at room temperature shows increased hardness of the SR method grown crystal. Second harmonic generation efficiency of SEST and SR grown crystals are 3.2 and 3.5 times greater than that of pure KDP. The Photoluminescence (PL) studies of Tb3+ ions result from the radiative intra-configurational f-f transitions that occur from the 5D4 excited state to the 7Fj (j=6, 5, 4, 3) ground states. The decay curve of the 5D4 level of emission was observed with a long life time of 319.2041μs for the SR grown Tb3+:LHHC crystal.

A simple theoretical approach to analyze the second harmonic generation of single crystals

Single crystals also play a vital role in the emerging technologies such as lasers, light emitting diodes, fibre optic communication components, solar cell, nonlinear optical devices, microelectronic components, transducers, memory elements and pyroelectric detectors. These are all the part of solid state devices that exist due to strong influence of single crystals as a result of recent development in technologies. Growth of large size single crystals of l-histidine hydrochloride monohydrate (LHHM) grown from aqueous solution by slow evaporation technique. Single crystal X-ray diffraction studies confirm that the grown crystal belongs to orthorhombic crystal system with space group P212121. The electrical properties such as plasma energy, Penn gap, Fermi energy and polarizability were calculated to analyze second harmonic generation (SHG). In addition, nonlinear optical properties were already performed to confirm the SHG efficiency of the grown crystal. Hence, LHHM is an excellent NLO material with enhanced SHG efficiency required for important applications in the field of optoelectronic and photonics.

Deuterium MAS NMR studies of dynamics on multiple timescales: histidine and oxalic acid.

Deuterium ((2) H) magic-angle spinning (MAS) nuclear magnetic resonance is applied to monitor the dynamics of the exchanging labile deuterons of polycrystalline L-histidine hydrochloride monohydrate-d7 and α-oxalic acid dihydrate-d6 . Direct experimental evidence of fast dynamics is obtained from T1Z and T1Q measurements. Further motional information is extracted from two-dimensional single-quantum (SQ) and double-quantum (DQ) MAS spectra. Differences between the SQ and DQ linewidths clearly indicate the presence of motions on intermediate timescales for the carboxylic moiety and the D2 O in α-oxalic acid dihydrate, and for the amine group and the D2 O in L-histidine hydrochloride monohydrate. Comparison of the relaxation rate constants of Zeeman and quadrupolar order with the relaxation rate constants of the DQ coherences suggests the co-existence of fast and slow motional processes.

Investigations on the growth aspects and characterization of semiorganic nonlinear optical single crystals of l-histidine and its hydrochloride derivative

Semiorganic single crystals of l-histidine and l-histidine hydrochloride monohydrate have been obtained in a single solution prepared from the mixture of l-histidine and hydrochloric acid in 1:2M ratio. Growth aspects of the single crystals have been discussed along with characterization studies. Crystal system and lattice parameters have been identified by X-ray diffraction analyses. It has been observed that the grown crystals possess orthorhombic system but with different set of lattice parameters. Presence of various functional groups has been identified and formation of two different crystals has been confirmed by Fourier transform infrared spectral analyses and FT-Raman studies. Linear and nonlinear optical properties have been studied by UV–Vis spectral analyses and Kurtz–Perry powder technique respectively. The thermal stability of the grown crystals was determined by thermal analyses. From the characterization studies it is found that both the crystals are useful for second harmonic generation applications.

Effect of Ni2+ Doping on the Growth and Properties of Mn-L-Histidine Hydrochloride Monohydrate Crystals

The main focus of this work had been to grow good quality crystals from amino acids and amino acid-based materials for nonlinear optics (NLO) applications. For the first time, a series of amino acid complexes doped with transition metal ions were grown in our laboratory from aqueous solutions by slow evaporation technique. Ni(II) ion doped Manganese L-Histidine hydrochloride monohydrate (Ni(II)-MnLHICl) crystals were grown on the same lines and were characterized by powder X-ray diffraction (XRD), optical absorption, electron paramagnetic resonance, and infrared absorption studies. From Powder XRD, the unit cell lattice parameters were calculated as a=1.5301 nm, b=0.8928 nm and c=0.6851 nm. From electron paramagnetic resonance (EPR) spectra, isotropic “g” factor and spin hamiltonian parameter A all were calculated as 2.0439 and 20×10−4, respectively. From optical absorption studies, crystal field splitting value (Dq) and the interelectron repulsion parameters B and C were calculated for Ni2+ and Mn2+ as Dq=850 cm−1, B=725 cm−1, C=2640 cm−1 and Dq=915 cm−1, B=810 cm−1, C=2780 cm−1, respectively. The presence of various functional groups and the modes of vibrations were confirmed by FTIR studies.

C-REDOR curves of extended spin systems

The convergence of simulated C-REDOR curves of (infinitely) large spin systems is investigated with respect to the number of spins considered in the calculations. Taking a sufficiently large number of spins (>20,000 spins) into account enables the simulation of converged C-REDOR curves over the entire time period and not only the initial regime. The calculations are based on an existing approximation within first order average Hamiltonian theory (AHT), which assumes the absence of homonuclear dipole–dipole interactions. The C-REDOR experiment generates an average Hamiltonian close to the idealized AHT behavior even for multiple spin systems including multiple homonuclear dipole–dipole interactions which is shown from numerically exact calculations of the spin dynamics. Experimentally it is shown that calculations accurately predict the full, experimental C-REDOR curves of the multi-spin systems 31P–19F in apatite, 31P–1H in potassium trimetaphosphimate and 1H–31P in potassium dihydrogen phosphate. We also present 13C–1H and 15N–1H data for the organic compounds glycine, l-alanine and l-histidine hydrochloride monohydrate which require consideration of molecular motion. Furthermore, we investigated the current limits of the method from systematic errors and we suggest a simple way to calculate errors for homogeneous and heterogeneous samples from experimental data.

Crystal growth and characterization of l-histidine hydrochloride monohydrate semiorganic nonlinear optical single crystals

Nearly perfect single crystals of l-histidine hydrochloride monohydrate have been grown from the solution prepared from the mixture of l-histidine and hydrochloric acid using slow evaporation solution growth technique. Single crystal X-ray diffraction analysis, High resolution X-ray diffraction analysis, fourier transform infrared and FT-Raman analyzes were employed for structural characterization. Linear and nonlinear optical properties have been studied by UV–Vis transmission spectrum and Kurtz Perry technique respectively. The refractive index, redox behavior and hardness of the grown crystal have been found by suitable methods. Thermogravimetric, differential thermal analysis were employed to characterize the as-grown crystals. The second harmonic generation conversion efficiency of the grown crystal and other properties show the suitability of the grown crystal for frequency conversion applications.

Crystal Growth, Optical and Dielectric Properties of L-Histidine Hydrochloride Monohydrate Nonlinear Optical Single Crystals

Optically transparent and bulk single crystal of l-histidine hydrochloride monohydrate (LHHC) was successfully grown by slow evaporation technique. The cell parameters and the crystallinity of the grown crystal were estimated by the single-crystal. Optical transmittance of the crystal was recorded using the UV–vis–NIR spectrophotometer. The optical band gap and optical constant of the material were determined by using transmission spectrum. The dielectric loss and dielectric constant measurements as a function of frequency and temperature were measured for the grown crystal.

Spectral, optical, and thermal studies of pure and Zn(II)-doped l-histidine hydrochloride monohydrate (LHHC) crystals

The influence of doping the transition metal Zn(II) on the growth, spectral, optical, and thermal properties of l-histidine hydrochloride monohydrate (LHHC) crystals grown by slow solvent evaporation method has been investigated. Structural characterizations of the grown crystals were carried out by single crystal X-ray diffraction analysis and it shows slight structural changes as a result of doping. The FT-IR spectral study reveals the presence of various functional groups and confirms the slight distortion of the structure of the crystals due to doping. The energy dispersive X-ray analysis reveals the incorporation of Zn(II) in the crystalline matrix of LHHC crystal. The UV–Vis spectral study was carried out to analyze the optical transmittance of the grown crystals and found that the transmittance is very high in the visible and UV regions for both pure and doped crystals. The second harmonic generation (SHG) for the grown crystals was confirmed by Nd:YAG laser. The scanning electron microscopy reveals the presence of defect centers and crystal voids. The thermal stability and purity of the grown crystals were analyzed by thermogravimetry, differential thermal analysis, and differential scanning calorimetry techniques.

High-pressure Raman spectra of l-histidine hydrochloride monohydrate crystal

Single-crystals of l-histidine hydrochloride monohydrate, C 6H 9N 3O 2·HCl·H 2O, were studied by Raman spectroscopy as a function of pressure in a diamond anvil cell up to 7.5 GPa at room temperature over the spectral range 3450–30 cm −1. The effect of changing pressure on the vibrational spectrum is discussed. From the analysis of results we inferred that the crystal undergoes a reversible structural phase transition between 2.7 and 3.1 GPa. This transition is characterized by the splitting of a band related to torsion of CO 2 −, the disappearance and appearance of modes related with stretching of OH − and deformation of CO 2 −, as well as with bands of low wavenumber which are assigned as lattice modes, and by the discontinuities of the curves of wavenumber versus pressure. Pressure coefficients for all modes observed in this work are also given.