Tris-sarcosine Calcium Chloride Research Articles

Effects of Composition and Compression Pressure on the Ferroelectricity of a Novel Eco-Friendly Nanocomposite Based on a Molecular Ferroelectric of Tris-Sarcosine Calcium Chloride Filled with Cellulose Nanoparticles

For the first time, to our knowledge, an eco-friendly nanocomposite based on a classical molecular ferroelectric of Tris-sarcosine calcium chloride (TSCC) with an addition of cellulose nanoparticles (CNPs) was synthesized. The samples containing different cellulose concentrations were compressed under various pressures from 0.1 to 0.7 GPa to investigate the effects of composition and compression pressure on the ferroelectricity of the composites. Experiments were conducted on samples in the fresh state and after 200 h under normal conditions. The results obtained demonstrated higher phase transition temperatures in the composites than those of pure TSCC. Besides, a deformation of the dielectric hysteresis loops with changing cellulose content was detected. Importantly, an increase in compression pressure applied on the samples led to the movement of the phase transition point toward higher temperatures. The results also revealed an instability of the ferroelectric properties in the composites with high content of cellulose.

Calculation of the Halfwidth and the Activation Energy for the Soft Raman Modes in the Brominated Compounds of Tris-Sarcosine Calcium Chloride

This letter contributes how to calculate the anomalous behavior for the damping constant (halfwidth) of the ferroelectric Tris-Sarcosine Calcium Chloride (TSSC) and its brominated compounds TSSC1−xBrx (x = 0.13, 0.42 and 0.60) from the wavenumber data of the soft modes below the phase transition temperature of TC. The pseudospin-phonon coupled (PS) and the energy fluctuation (EF) models derived from the dynamical Ising model were used. Both PS and EF models have been used to contribute understanding the temperature dependence of the phase transition mechanism of TSSC1−xBrx. In addition, values of the activation energy for TSSC1−xBrx (x = 0, 0.13, 0.42 and 0.60) were extracted from the damping constant as calculated from both models (PS and EF). Our results indicate order-disorder type phase transition for TSSC1−xBrx.
 HIGHLIGHTS
 
 This work contributes how to calculating the critical behavior of the halfwidth for the soft Raman modes in ferroelectric TSSC1-xBrx (x = 0, 0.13, 0.42 and 0.60) liquid crystals from their observed wavenumbers data. Also, the values of the activation energy close to the ferroelectric-paraelectric phase transition of these crystals was deduced.
 This calculation of the halfwidth and the activation energy were performed using the pseudospin-phonon coupled (PS) and the energy fluctuation (EF) models in the ferroelectric phases (T < TC) of the crystals studied here.
 
 GRAPHICAL ABSTRACT

Investigation on certain optical, thermal, and Z-scan studies of nonlinear optical tris–sarcosine calcium chloride single crystal

Investigation on certain optical, thermal, and Z-scan studies of nonlinear optical tris–sarcosine calcium chloride single crystal

New sarcosine–metal halide complexes related to ferroelectric TSCC

A family of sarcosine–metal halide coordination polymers are presented. All have structural similarities to the well-known ferroelectric,trissarcosine calcium chloride, though all these example have centrosymmetric crystal structures.

Ferrielectricity in the metal-organic ferroelectric tris-sarcosine calcium chloride

We report ferrielectricity in a single-phase crystal, TSCC -- tris-sarcosine calcium chloride [(CH3NHCH2COOH)3CaCl2]. Ferrielectricity is well known in smectic liquid crystals but almost unknown in true crystalline solids. Pulvari reported it in 1960 in mixtures of ferroelectrics and antiferroelectrics, but only at high fields. TSCC exhibits a second-order displacive phase transition near Tc = 130 K that can be lowered to a Quantum Critical Point at zero Kelvin via Br- or I-substitution, and phases predicted to be antiferroelectric at high pressure and low temperatures. Unusually, the size of the primitive unit cell does not increase. We measure hysteresis loops and polarization below T = 64 K and clear Raman evidence for this transition, as well of another transition near 47-50 K. X-ray and neutron studies below Tc = 130K show there is an antiferroelectric displacement out of plane of two sarcosine groups; but these are antiparallel displacements are of different magnitude, leading to a bias voltage that grows with decreasing T. A monoclinic subgroup C2 may be possible at the lowest temperatures (T<64K or T<48K), but no direct evidence exists for a crystal class lower than orthorhombic.

Searching for new ferroelectrics and multiferroics: A user’s point of view

AbstractA perspective on computational studies of ferroelectrics and multiferroics is given that emphasises what has yet to be done, along with some subtleties in previously studied systems. Beginning with the extensive data-mining studies of Abrahams and more recently, Rabe, a survey is given of magnetostrictive effects in antiferromagnetic antiferroelectrics (after Toledano and Toledano), which has an nonmagnetic analogy in the antiferroelectric phase of tris-sarcosine calcium chloride and a reminder of the unusual spin–phonon coupling of Holden et al. in systems such as KCoF3 and EuTiO3. Attention is also paid to field-temperature phase diagrams, finite non-periodic boundary conditions, and processing-dependent structures.

Quantum criticality in a uniaxial organic ferroelectric

Tris-sarcosine calcium chloride (TSCC) is a highly uniaxial ferroelectric with a Curie temperature of approximately 130 K. By suppressing ferroelectricity with bromine substitution on the chlorine sites, pure single crystals were tuned through a ferroelectric quantum phase transition. The resulting quantum critical regime was investigated in detail and was found to persist up to temperatures of at least 30–40 K. The nature of long-range dipole interactions in uniaxial materials, which lead to non-analytical terms in the free-energy expansion in the polarization, predict a dielectric susceptibility varying as 1/T3close to the quantum critical point. Rather than this, we find that the dielectric susceptibility varies as 1/T2 as expected and observed in better known multi-axial systems. We explain this result by identifying the ultra-weak nature of the dipole moments in the TSCC family of crystals. Interestingly, we observe a shallow minimum in the inverse dielectric function at low temperatures close to the quantum critical point in paraelectric samples that may be attributed to the coupling of quantum polarization and strain fields. Finally, we present results of the heat capacity and electro-caloric effect and explain how the time dependence of the polarization in ferroelectrics and paraelectrics should be considered when making quantitative estimates of temperature changes induced by applied electric fields.

Critical exponents for anisotropic thermal expansion at ferroelectric Curie temperatures: Evidence for defect mechanisms

The defect dynamical model of Sigov and Levanyuk is used to analyze a heretofore unsolved problem in ferroelectricity: the temperature change of anisotropic thermal expansion along the polar axis. For brominated tris-sarcosine calcium chloride a new expansion exponent in reduced temperature is found, in agreement with the Sigov-Levanyuk theoretical value, under the assumption that the change in thermal diffusion is proportional to the change in thermal expansion near Tc.

The perfect soft mode: giant phonon instability in a ferroelectric

Previous studies of unstable (‘soft’) optical modes in ferroelectrics have reported minimum frequencies of 1 cm−1 (30 GHz) for underdamped phonons. In this work we fabricate a cylindrical coaxial specimen and rectangular plate waveguide specimens of tris-sarcosine calcium chloride (TSCC) and follow its soft mode several orders of magnitude lower to 1 GHz. Below 30 GHz the relaxation time is probably characteristic of domain wall motion; the new theory of Pakhomov et al (2013 Ferroelectrics at press) predicts 0.5 THz far from TC and a (T − TC)/TC dependence, in agreement with our experimental values. This discovery has implications for GHz electronics such as phased array radar or other voltage-tunable low-loss components. The mean-field frequency description of the soft mode response f(T) is supported via precision calorimetry on TSCC with and without Br-doping. The ferroelectric–antiferroelectric phase transition, previously suggested from high-pressure data, is confirmed at 45 K at 1 atm.

Phase diagram and phase transitions in ferroelectrictris-sarcosine calcium chloride and its brominated isomorphs

Tris-sarcosine calcium chloride [(TSCC), (${\mathrm{CH}}_{3}{\mathrm{NHCH}}_{2}\mathrm{COOH}){}_{3}{\mathrm{CaCl}}_{2}$] is a uniaxial ferroelectric (FE) with a displacive second-order phase transition near ${T}_{c}=130$ K. A continuous range of solid solutions can be made by substituting Br for Cl, which lowers ${T}_{c}$ to 0 K at \ensuremath{\sim}72% Br. Such a quantum critical point differs from that in pseudocubic FEs, such as O-18 SrTiO${}_{3}$ or doped KTaO${}_{3}$. For many years, this system was thought to have only two phases, paraelectric and FE, at ambient pressure. However, we find from dielectric and resonant ultrasound spectroscopy that there are four phase transitions in TSCC and in TSCC:Br (for 0 Br 40%): Order-disorder of the sarcosine methyl group at 185 K; displacive FE transition at 130 K (in pure TSCC); a second FE transition [previously hypothesized to be antiferroelectric (AFE) but probably not] at 64 K; and a new anomaly at \ensuremath{\sim}45 K which might be due to a phase transition or to Debye-like freezing of orientational disorder of some part of the sarcosine molecule. The probable sequence of structures is (upon cooling): Pnma with $Z=4({D}_{2h}^{16})$ ambient 500 K &gt; $T$ &gt; 185 K, disordered; Pnma with $Z=4({D}_{2h}^{16})185 \mathrm{K}T130 \mathrm{K}$ (ordered); $\mathit{Pn}{2}_{1}a$ with $Z=4({C}_{2v}^{9})130 \mathrm{K}T64 \mathrm{K}$ (FE); $P{2}_{1}a$ $({C}_{2h}^{5})$ with $Z$ $=$4, 64 K &gt; $T$ &gt; 45 K (not AFE); $T$ 45 K, unknown structure. A sixth hexagonal structure at high temperatures (&gt;500 K) is hypothesized to be ${D}_{6h}^{3}$(P6${}_{3}$/mcm) with $Z$ $=$2, but the samples decompose first at 503 K (230 \ifmmode^\circ\else\textdegree\fi{}C).

EPR of Cu2+-doped tris-sarcosine calcium chloride

The EPR study of the Cu2+-doped tris-sarcosine calcium chloride (TSCC) at room temperature is reported. Two magnetically inequivalent sites for Cu2+ were observed. The rhombic spin Hamiltonian parameters are determined by fitting the EPR spectra for two centres: Cu2+(I) g1 = 2.0276, g2 = 2.0517, g3 = 2.4019, A1 = 82, A2 = 128, A3 = 152 [G] and Cu2+(II) g1 = 2.0231, g2 = 2.0368, g3 = 2.5294, A1 = 76, A2 = 92, A3 = 156 [G]. The ground state wave function is also determined. The g-anisotropy is evaluated and compared with the experimental value. Further, the optical study of the crystal at room temperature is carried out and the nature of bonding in the complex is discussed.

Trissarcosine barium(2 + ) dibromide—a new complex of N‐methylglycine

AbstractWe obtained a new complex containing sarcosine (CH3NH2+CH2COO−) and barium(2 + ) dibromide (TSBB) in 3:1 molar ratio, as well as its deuterated analog. Single‐crystal X‐ray diffraction measurements show that TSBB crystallizes in the monoclinic system, space group P2(1)/c. The unit cell parameters are as follows: a = 18.345(4) Å, b = 10.668(2) Å, c = 8.9212(18) Å, β = 91.86(3)°, and Z = 4. The structure was determined with final R1 = 0.0396 (for I &gt; 2σI). The crystal possesses a pseudohexagonal symmetry down c axis showing the resemblance to the crystal structure of trissarcosine calcium chloride (TSCC). There are NHBr hydrogen bonds (HB) of six types. TSBB crystal undergoes a phase transition at 416 K (heating)–415 K (cooling) of continuous nature. The spectroscopic [Infrared (IR) and Raman] investigation of the crystal was performed at room temperature. The results are discussed with respect to the crystallographic data, as well as the results obtained for TSCC crystal. Copyright © 2008 John Wiley &amp; Sons, Ltd.

1H NMR study of the phase transitions of trissarcosine calcium chloride single crystals at low temperature

The 1H NMR line-width and spin–lattice relaxation time T 1 of TSCC single crystals were studied. Variations in the temperature dependence of the spin–lattice relaxation time were observed near 65 and 130 K, indicating drastic alterations of the spin dynamics at the phase transition temperatures. The changes in the temperature dependence of T 1 near 65 and 130 K correspond to phase transitions of the crystal. The anomalous decrease in T 1 around 130 K is due to the critical slowing down of the soft mode. The abrupt change in relaxation time at 65 K is associated with a structural phase transition. The proton spin–lattice relaxation time of this crystal also has a minimum value in the vicinity of 185 K, which is governed by the reorientation of the CH 3 groups of the sarcosine molecules. From this result, we conclude that the two phase transitions at 65 and 130 K can be discerned from abrupt variations in the 1H NMR relaxation behavior, and that 1H nuclei play important roles in the phase transitions of the TSCC single crystal.

High-Field Chlorine NMR Spectroscopy of Solid Organic Hydrochloride Salts: A Sensitive Probe of Hydrogen Bonding Environment

A series of organic hydrochloride salts has been investigated using solid-state 35Cl and 37Cl NMR spectroscopy at applied magnetic field strengths of 9.4 and 18.8 T. Magic-angle spinning, static Hahn-echo, and quadrupolar Carr−Purcell Meiboom−Gill (QCPMG) echo experiments have been applied to investigate the chlorine electric field gradient (EFG) and chemical shift (CS) tensors for l-tyrosine hydrochloride, l-cysteine methyl ester hydrochloride, l-cysteine ethyl ester hydrochloride, quinuclidine hydrochloride, and tris sarcosine calcium chloride. Chlorine-35 nuclear quadrupolar coupling constants for these compounds range from 2.23 to 5.25 MHz, and isotropic chemical shifts range from approximately 9 to 53 ppm relative to the chloride ion in aqueous solution. The results demonstrate the feasibility and benefits of high-field 35/37Cl NMR studies of organic chloride salts. A discussion of the data in the context of the known X-ray or neutron diffraction structures for these compounds suggests that the chlor...

A New Nuclear-Quadrupole Double-Resonance Technique based on Solid Effect

Abstract A new nuclear-quadrupole double-resonance technique is described. It has a higher sensitivity and a higher resolution than the conventional nuclear-quadrupole double-resonance technique based on solid effect. The new technique involves magnetic field cycling between a high and a low static magnetic field and simultaneous application of two rf magnetic fields when the sample is in the low static magnetic field. A strong rf magnetic field induces "forbidden" simultaneous transitions in a magnetic (usually 1H) and in a quadrupole spin system and thus couples the two spin systems. A weak rf magnetic field induces transitions between the energy levels of the quadrupole nuclei and simulates a fast spin-lattice relaxation of the quadrupole nuclei when its frequency matches an NQR frequency. The sensitivity and resolution of the new technique are discussed and test measurements in tris-sarcosine calcium chloride are presented.

A far-infrared spectroscopic study of low temperature soft phonon mode in Tris-Sarcosine Calcium Chloride(TSCC)

Abstract Temperature dependences of the soft phonon frequency and the damping constant in Tris-Sarcosine Calcium Chloride (TSCC) single crystal have been investigated between 5K and 100K by using a Fourier-transform far-infrared spectrometer. It has been observed that the soft phonon frequency decreases gradually and the damping constant increases as the transition temperature is approached from below The damping constant varies from 7cm−1 a 90K to less than 0.5cm−1 at 5K. It has been found that the damping constant is approximately proportional to temperature below about 60K.

Thermal diffuse scattering in time-of-flight neutron diffraction studies on SBN and TSCC single crystals

Thermal diffuse scattering (TDS) from single crystals of barium strontium niobate (SBN) and from a partly deuterated single-crystal of tris(sarcosine) calcium chloride (TSCC) measured on the time-of-flight (TOF) Lane single-crystal diffractometer DN-2/IBR-2, Dubna, Russia, are presented. Various characteristic distributions of the TDS were measured and could be interpreted for the elastically (nearly) isotropic SBN crystals as well as for the anisotropic TSCC sample in accordance with the theory. The velocities of sound propagation are determined in both cases. Temperature-dependent changes of the TDS are qualitatively analysed for SBN crystals.

NMR Investigations of Molecular Motions and Critical Dynamics at the Ferroelectric Phase Transition of Tris‐Sarcosine Calcium Chloride

Abstract35Cl and 81Br quadrupolar perturbed NMR measurements in single crystals of tris‐sarcosine calcium bromide (TSCB) and tris‐sarcosine calcium chloride (TSCC) are used to study molecular motions and the dynamical critical behaviour near the ferroelectric phase transition of TSCC. At temperatures higher than about 130 K the spin‐lattice relaxation time T1 of 81Br nuclei in TSCB is dominated by an activated process with an activation energy of 28 kJ/mol which is attributed to the reorientation of parts of the sarcosine molecule. The results are compared with those obtained from 35Cl measurements of TSCC. Near the ferroelectric phase transition of TSCC at 131.5 K a critical contribution to the 35Cl spin‐lattice relaxation rate is observed which can be explained on the basis of the standard mean‐field model in accordance with the static critical behaviour below Tc.

Phase transitions in tris-sarcosine calcium chloride (TSCC) to 14 GPa

Abstract The capacitance of samples of tris-sarcosine calcium chloride (TSCC) has been measured at room temperature at pressures up to 14 GPa. A diamond anvil cell was employed to control the pressure. Experimental results indicate that TSCC undergoes two phase transitions, near 1.3 GPa and 4.1 GPa.

Dipolar and higher order interactions in ferroelectric tscc

Abstract Relevant data on Tris-Sarcosine Calcium Chloride (TSCC), including temperature dependent data of spontaneous polarization (P = 0.27 μC/cm2), dielectric permittivity (Curie constant at T > TcC = 59 K, and Curie temperature Tc = 125.4 K) and specific heat (δCp = 0.27 × 106 erg/K cm3, specific heat jump at T = Tc after discounting for logarithmic corrections) have been analyzed within the framework of the effective field approach to ferroelectric transitions, resulting in N = 1.01 × 1021 dipoles/cm3 and μ = 0.80 × 10−18 esu cm, in good agreement with microscopic observations. Consideration of quadrupolar (g ≠ 0) and octopolar (h ≠ 0) contributions to the effective field improve the theoretical fit to (Ps /Pso ) vs. (T/Tc ) data.