Triclinic Lattice Research Articles

Synthesis, structural, DFT studies, docking and antibacterial activity of a xanthene based hydrazone ligand

Herein, we present the synthesis of novel xanthene-based hydrazone (1). The chemical structure of 1 was resolved using spectroscopic techniques such as NMR, FT-IR, UV-VIS and X-ray crystallographic approaches. X-ray diffraction analysis shows that the compound (1) crystallizes in triclinic crystal lattice with the P¯1 space group and diffused to form multi-layered structure due to non-covalent interactions such as intramolecular hydrogen bonding (H.B). In addition to experimental investigation, density functional theory (DFT) calculation with M06-2X/6-31G(d,p) and B3LYP/6-31G(d,p) level of theories was performed on compound (1) to obtain optimized geometry, spectroscopic and electronic properties. DFT optimized geometry shows good agreement with the experimental XRD structure. The hyper conjugative interactions and hydrogen bonding network are responsible for the stability of compound (1) as revealed by natural bond orbital (NBO) calculation. Moreover, hydrogen bonding network in the dimer is confirmed by FT-IR and thermodynamic studies showing excellent agreement with XRD and NBO findings. TD-DFT/UV-VIS analysis provides insight that maximum excitation is found in 1 which shows good agreement with experimental UV-VIS result. The global reactivity parameters are calculated using the energies of frontier molecular orbitals also disclosed that the compound is more stable might be due to hydrogen bonding network. Experimental and molecular docking studies indicated that this compound has anti-bacterial and anti-diabetic properties. The binding affinity of this compound against the multidrug efflux pump subunit AcrB OS=Escherichia coli (strain K12) and Human Pancreatic Alpha-Amylase is −9.2 and −10.00 kcal/mol which are higher than the control drugs. Pi-Pi, Pi-anaion, amide-pi and pi-alkyl bonds play key role in drug-protein complexes.

Syntheses, crystal structures, and magnetic properties of two new organic-inorganic hybrid materials containing metal-bis(dithiolene) anion and substituted triphenylphosphinium

Two new organic-inorganic hybrid materials, [(Ph)2CHTPP][Ni(mnt)2](1) and [(Ph)2CHTPP]2[Cu(mnt)2]·2CH3CN(2) (mnt=maleonitriledithilate, [(Ph)2CHTPP]+=diphenylmethane-triphenylphosphinium), were prepared and characterized. Two compounds crystallize in the triclinic lattice with P-1 space group, and the adjoined anions form one-dimension chain structure through weak π⋯π or C⋯N interactions in 1, and CH⋯S and CH⋯N hydrogen bonds through the solvent lattice acetonitrile molecule in 2. The power X-ray diffraction patterns are in good agreement with the simulated patterns based on the crystal structures, indicating the purity of the as-grow crystals. FT-IR and UV–vis spectra were recorded and analyzed with the aid of the DFT calculation. The HOMO/SOMO and LUMO energy gaps were calculated by the DFT method explain charge transfer interactions take place within two materials. Thermal analysis shows two materials can be stable up to 171°C for 1 and 215°C for 2. The variable-temperature susceptibility analysis shows that 1 is the para-magnetic system with a spin-gap at 110K and 2 exhibits a weak antiferromagnetic exchange interaction as the temperature is lowered.

Triclinic crystal structure distortion of multiferroic BiMn7O12.

The quadruple perovskite BiMn7O12 obtained via high-pressure synthesis was investigated by high-resolution synchrotron X-ray powder diffraction over a temperature range of 10 to 295 K. Careful Rietveld analysis reveals triclinic lattice distortion of BiMn7O12 at 295 K, which increases upon cooling to 10 K. Also hkl-dependent anisotropic Bragg reflection shape was introduced to give a precise description of the diffracted intensities. Importantly BiMn7O12 crystal structure was described in the non-centrosymmetric I1 triclinic space group. We also demonstrate the use of irreducible representations analysis (ISODISTORT program) for crystal structure distortion from Im to I1 space group. The irreducible representation which describes crystal structure distortion points towards possible ferroelectricity. Finally anisotropic thermal lattice expansion was observed.

Polymorphs of spin-crossover iron(II) complex fac-[FeII(HLn-Pr)3]Cl·PF6 (HLn-Pr = 2-methylimidazol-4-yl-methylideneamino-n-propyl): Assembly structures and scan rate dependent spin-crossover properties with thermal hysteresis

Two polymorphs of iron(II) complex fac-[FeII(HLn-Pr)3]Cl·PF6, 1 and 2, were obtained (HLn-Pr=2-methylimidazole-4-yl-methylideneamino-n-propyl ligand). Complex cations, fac-[FeII(HLn-Pr)3]2+, of 1 and 2 had similar octahedral and facial geometries coordinated with three bidentate HLn-Pr ligands. The three imidazole groups in fac-[FeII(HLn-Pr)3]2+ with Δ- and Λ-enantiomorphs are hydrogen-bonded with three Cl− ions, forming one-dimensional (1D) and two-dimensional (2D) network structures in 1 and 2, respectively. Complex 1 had a ladder-like 1D structure formed by imidazole⋯chloride hydrogen bonds, with a circular binuclear net unit of {⋯fac-[FeII(HLn-Pr)3]2+⋯Cl−⋯}2, and showed two successive scan rate dependent spin crossover (SCO) processes with thermal hysteresis. Complex 2 had a 2D network structure formed by imidazole⋯chloride hydrogen bonds with circular binuclear and tetranuclear net units of {⋯fac-[FeII(HLn-Pr)3]2+⋯Cl−⋯}2,4, and showed a one-step scan rate dependent SCO profile centered at 143K with thermal hysteresis. The relaxation property was identified from the scan rate dependence of magnetic susceptibility and temperature dependent Mössbauer spectra and X-ray diffraction studies. The crystal structure of 2 was analyzed at 12 temperatures in a cooling cycle. Upon lowering the temperature, the crystal system transformed from a monoclinic to a triclinic lattice at 210K in a high-spin state, and then transformed to a low-spin state at 150K in the triclinic system.

Experimental and theoretical second harmonic generation and photoluminescence from the pseudo-centrosymmetric dihydrochloride salt dihydrate of trans-1,2-bis(4-pyridyl)ethene

Here we have prepared a dihydrochloride salt dihydrate of the well-known trans-1,2-bis(4-pyridyl)ethene (BPE) featuring both photoluminescent and nonlinear optical properties. In its triclinic lattice (space group P1), BPE cations are stacked face-to-tail through π⋯π interactions between the spacer double-bonded carbons and the protonated pyridyl ring, with a slippage of 3.45 A always towards the same direction, which is common in other NLO crystals. The existence of inversion symmetry was suggested in its crystal structure, which was ruled out by the SHG emission centred at 487 nm upon excitation at 974 nm. While the fully optimized single molecule of the divalent BPE cation in the gas phase had almost null μ, βtot, βCT and βvec values calculated at the CAM-B3LYP/NLO-V//B3LYP/6-31G* level of theory, these values differed from zero in the crystal conformation. More interestingly, a ca. 4-fold increase in βtot, α and μ was observed for the π⋯π stacked four-molecules as found in its crystal structure. Lastly, this BPE material presents high photoluminescence emission centred at 425 nm under excitation at 366 nm, being therefore a multifunctional optical crystal form.

Single crystal preparation and x-ray structure analysis of non-peripherally alkyl-substituted phthalocyanine blends

Single crystals of non-peripherally alkyl-substituted macrocycle molecules, such as octahexylphthalocyanine (C6PcH2), octapentylphthalocyanine (C5PcH2), octahexyltetrabenzotriazaporphyrin (C6TBTAPH2), and their blends were prepared. The crystal structures of C6PcH2 and C5PcH2, which were determined by single-crystal X-ray structure analysis, were identified as monoclinic lattices, while that of C6TBTAPH2 was identified as a triclinic lattice. Despite the similarity between the crystal structures of C6PcH2 and C5PcH2, the single crystals grown from the blended solutions of C6PcH2 and C5PcH2 were based on a triclinic lattice. On the other hand, in the case of the single crystals composed of C6PcH2 and C6TBTAPH2, another type of crystal structure did not appear. The crystal structures of these single crystals are discussed by taking the differences in the alkyl-substituent length and the core structure into consideration.

Iron arsenide superconductors (CaFeAs)10MnAs8 with metallic interlayers (M = Pt, Pd; n = 3, 4)

The compounds referred to as 1038 and 1048 phases (CaFeAs)10PtnAs8 (n = 3,4) are the structurally most complex iron arsenide superconductors and the first examples with metallic interlayers. The electronic subsystems of FeAs and PtnAs8 layers hardly interact and the contribution of the metallic PtnAs8 interlayers to the Fermi surface is so small that the typical nesting is not degraded. (CaFeAs)10Pt3As8 is the parent compound of the 1038/1048 materials which undergoes the typical magneto‐structural phase transition in spite of the already triclinic lattice. Superconductivity is controlled by the same doping mechanisms as known from simpler FeAs systems. High critical temperatures up to 38 K occur in both 1038 and 1048 phases if the FeAs layers are clean (free from Pt) and electron doped by charge transfer either from Pt4As8 in 1048 or by rare‐earth doping of the calcium layer in 1038 compounds. The presence of two negatively charged layers (FeAs)δ− and (PtnAs8)δ− which compete for the electrons transferred from the Ca2+ ions is unique in the family of iron arsenide superconductors. Geometric incompatibilities of the FeAs and PtnAs8 slabs cause severe stacking disorder. The robustness of superconductivity against low lattice symmetry and significant structural imperfection of the interlayer is quite remarkable and underlines that the FeAs slabs are the key in controlling and understanding high‐temperature superconductivity in iron arsenides.Crystal structure of (CaFeAs)10Pt3As8 and the Pt3As8 layer.

Synchrotron powder diffraction, X-ray absorption and 1H nuclear magnetic resonance data for hypoxanthine, C5H4N4O

Synchrotron powder X-ray diffraction, X-ray absorption spectroscopy (XAS), and proton nuclear magnetic resonance (1H-NMR) data have been used to examine the structure of hypoxanthine, 1,7-dihydro-6H-purin-6-one (C5H4N4O), a purine base that participates in numerous metabolic processes. XAS and 1H-NMR spectroscopy were used to determine that hypoxanthine was present in its keto form (both in solid state and dissolved in an organic solvent). Rigid body refinement was performed with the Rietveld software package GSAS yielding triclinic lattice parameters of a = 7.1179 (2) Å, b = 9.7830 (3) Å, c = 10.4009 (3) Å, α = 58.876 (1)°, β = 67.609 (1)°, and γ = 71.937 (2)° (C5H4N4O, Z = 4, space group P$\bar 1$).

Synthesis, Thermal and Crystallographic Analysis of 1,1’-diylbis(2-Methyl-4-Phenylene)bis(2-Nitrobenzoate)Cyclohexane

The crystal structure of 1,1’-diylbis (2-methyl-4-phenylene) bis (2-nitrobenzoate) cyclohexane (NBM-2) has been determined by X-ray crystallographic technique. Single crystals were grown by slow evaporation technique. NBM-2 crystallized in the triclinic crystal lattice having space group P-1. Both the phenyl rings are perpendicular to the cyclohexane ring having chair conformation. NBM-2 showed both inter-and intramolecular interactions. The structure of NBM-2 has also been supported by FT-IR, 1HNMR, 13C NMR, MS techniques. The thermal behaviour of NBM-2 were studied by TGA and DSC techniques at heating rate of 10°C min-1 in nitrogen atmosphere. Thermal stability and kinetic parameters were determined according to Anderson-Freeman method and discussed.

Growth and characterization of new semiorganic nonlinear optical and piezoelectric lithium sulfate monohydrate oxalate single crystals

New semiorganic crystal of lithium sulfate monohydrate oxalate (LSO) for nonlinear application was synthesized by controlled slow evaporation method. The growth rate of various planes of the grown crystal was estimated by morphological study. Single crystal XRD analysis confirmed that the crystal belongs to triclinic lattice with space group P1. High transparency (∼95%) with large band gap (4.57eV) was analyzed by UV–vis studies. FTIR and Raman spectroscopy were used to identify various functional groups present in the LSO crystal. SHG efficiency was found to be equal to the KDP crystal. Thermal stability (up to 117.54°C) and melting point (242°C) of the crystal were studied by TG-DTA. In dielectric measurements, the value of dielectric constant decreases with increase in frequency. Hardness studies confirmed soft nature of crystals. The piezoelectric coefficient was found to be 6pC/N along [001].

Blue-Excited and Yellow-Emitting Oxynitride Phosphor Y6+(x/3)-yCay+(z/2)Si11N20+x-y+zO1-x+y-z:Ce

A novel yellow phosphor called Y6+(x/3)-yCay+(z/2)Si11N20+x-y+zO1-x+y-z:Ce that has an intensive blue excitation band was discovered. This phosphor, which can be synthesized relatively easily because it does not require high pressure or temperature, can be gained by firing at 1600°C for 4 hours under H2 5% + N2 95% gas flow. Rietveld refinement and SEM-EDX analysis revealed that the structure of Y6+(x/3)-yCay+(z/2)Si11N20+x-y+zO1-x+y-z:Ce is composed of a unique extensive (about 70%) substitution of Ca-O bonds for Y-N bonds in the Y6+(x/3) Si11N20-xO1+x structure having a triclinic lattice in the P31c space group. Y6+(x/3)-yCay+(z/2)Si11N20+x-y+zO1-x+y-z:Ce has shown yellow emission at 554 nm with 450-nm excitation and an FWHM of 147 nm. The wavelength of the excitation peak is 450 nm, which coincides with the wavelength of blue LED light. Due to having a broad yellow emission and an excitation band suitable for blue LED, the discovered phosphor is expected to be used in general lighting devices requiring high color rendering. The conditions for stably substituting Ca-O bonds for Y-N bonds are discussed.

Synthesis, Thermal and Crystallographic Analysis of 1,1’-diylbis(2-Methyl-4-Phenylene)bis(2-Nitrobenzoate)Cyclohexane

The crystal structure of 1,1’-diylbis (2-methyl-4-phenylene) bis (2-nitrobenzoate) cyclohexane (NBM-2) has been determined by X-ray crystallographic technique. Single crystals were grown by slow evaporation technique. NBM-2 crystallized in the triclinic crystal lattice having space group P-1. Both the phenyl rings are perpendicular to the cyclohexane ring having chair conformation. NBM-2 showed both inter-and intramolecular interactions. The structure of NBM-2 has also been supported by FT-IR, 1HNMR, 13C NMR, MS techniques. The thermal behaviour of NBM-2 were studied by TGA and DSC techniques at heating rate of 10°C min-1 in nitrogen atmosphere. Thermal stability and kinetic parameters were determined according to Anderson-Freeman method and discussed.

Bond competition and phase evolution on the IrTe₂ surface.

Compounds with incommensurate structural modulations have been extensively studied in last several decades. However, the relationship between structurally incommensurate/commensurate phases and associated electronic states remains enigmatic. Here we report the coexisting of complex incommensurate structures and highly unusual electronic roughness on the surface of in situ cleaved IrTe₂ by using scanning tunnelling microscopy/spectroscopy, corroborated with extensive density-functional theory calculations. This behaviour is traced to structural instability, which induces a structural transition from a trigonal to a triclinic lattice below transition temperature, giving rise to the formation of unidirectional structural modulations with distinct wavelengths, accompanied by the opening of a 'pseudo'-gap in the surface layer. With further cooling the surface adopts a structure that reflects an ~6 × periodicity that is different from the bulk 5 × periodicity. Calculations show that the structure distortion is not associated with a charge density wave, but is rather associated with Te p-electron bonding.

18-crown-6-sodium cholate complex: thermochemistry, structure, and stability.

18-Crown-6, one of the most relevant crown ethers, and sodium cholate, a steroidal surfactant classified as a natural bile salt, are components of a novel, synthesized coordination complex: 18-crown-6-sodium cholate (18C6·NaCh). Like crown ethers, bile salts act as building blocks in supramolecular chemistry to design new functionalized materials with a desired structure and properties. In order to obtain thermal behavior of this 1:1 coordination complex, thermogravimetry and differential thermal analysis were used, as well as microscopic observations and differential scanning calorimetry. Temperature dependent infrared (IR) spectroscopy gave a detailed view into phase transitions. The structures during thermal treatment were observed with powder X-ray diffraction, and molecular models of the phases were made. Hard, glassy, colorless compound 18C6·NaCh goes through crystalline-crystalline polymorphic phase transitions at higher temperatures. The room temperature phase is indexed to a triclinic lattice, while in the high temperature phases molecules take randomly one of the two different configurations in the unit cell, resulting in the 2-fold symmetry. The formation of cholesteric liquid crystalline phase occurs simultaneously with partial decomposition, followed by the isotropization with simultaneous and complete decomposition at much higher temperature, as obtained by IR. The results provide valuable information about the relationship between molecular structure, thermal properties, and stability of the complex, indicating the importance of an appropriate choice of cation, amphiphilic, and crown ether unit in order to synthesize compounds with desired behavior.

Structural, electronic and vibrational properties of N,N′-1H,1H-perfluorobutyl dicyanoperylenecarboxydiimide (PDI-FCN2) crystal

We present a theoretical and experimental investigation of the crystalline structure of N,N'-1H,1H-perfluorobutyl dicyanoperylenecarboxydiimide (PDI-FCN2) that has been deduced combining experimental XRD data, obtained from powders, with global-optimization algorithms which allow to identify Bravais lattice, primitive cell parameters, and space group of the crystal. The XRD spectrum calculated for the proposed crystalline structure very well reproduces the measured XRD data. Our results suggest the triclinic lattice structure of spatial groups P1 and P1, respectively, for the crystalline PDI-FCN2-1,7 and PDI-FCN2-1,6 isomers. In both cases, the primitive cell contains a single molecule. On the proposed crystalline structures, KS-DFT cell energy calculations, including van der Waals interactions, have been performed to assign the minimum energy geometrical structure and orientation of the molecule inside the corresponding primitive cell. These calculations evidence the molecular packing that characterizes the strong anisotropy of the PDI-FCN2 crystal. Electronic band-structures calculated for both isomers within the Kohn-Sham density-functional theory indicate that the crystalline P1 structure is an indirect gap semiconductor, while the P1 structure is a direct gap semiconductor. The electronic band structure calculations on the optimized crystal geometries highlight strong anisotropy in the dispersion curves E(k), which roots at the molecular packing in the crystal. Finally, the vibrational spectrum of both crystalline isomers has been calculated in the harmonic approximation and the dominant vibrational frequencies have been associated to collective motions of selected atoms in the molecules.

Origin of the phase transition in IrTe2: Structural modulation and local bonding instability

We used X-ray/neutron diffraction to determine the low temperature (LT) structure of IrTe2. A structural modulation was observed with a wavevector of k =(1/5, 0, 1/5) below Ts?285 K, accompanied by a structural transition from a trigonal to a triclinic lattice. We also performed the first principles calculations for high temperature (HT) and LT structures, which elucidate the nature of the phase transition and the LT structure. A local bonding instability associated with the Te 5p states is likely the origin of the structural phase transition in IrTe2.

Transition metal-doped lanthanum germanate apatites as electrolyte materials of solid oxide fuel cells

In this study, the effects of Fe, Mn, Ni, and Ti dopants on the densification, phase structure, microstructure, and electrical conductivity of the La 9.5 Ge 6.0 O 26.25 ceramics were examined. After sintering, the La 9.5 Ge 5.5 Mn 0.5 O 26 and La 9.5 Ge 5.5 Ti 0.5 O 26.25 ceramics displayed hexagonal symmetry while the La 9.5 Ge 5.5 Ni 0.5 O 25.75 and La 9.5 Ge 5.5 Fe 0.5 O 26 ceramics produced triclinic lattice. The La 9.5 Ge 5.5 Fe 0.5 O 26 ceramic sintered at 1400 °C showed the best electrical conductivity of 0.033 Scm − 1 and the lowest densification temperature among the apatite ceramics evaluated, and the calculated thermal expansion coefficient of this system emerged to be 10.5 × 10 − 6 K −1 , compatible with those of the common adjacent materials used in solid oxide fuel cells (SOFCs). Single cells of NiO-SDC/La 9.5 Ge 5.5 Fe 0.5 O 26 /LSCF-SDC were built and evaluated. The open circuit voltages of the single cell read 0.96 and 1.01 V respectively at 950 and 800 °C, both in accord with the redicted theoretical values and verifying the pure ionic conduction in apatites. The maximum power densities (MPDs) of the single cell were 0.384, 0.280, 0.201, and 0.125 Wcm − 2 respectively at the measurement temperatures of 950, 900, 850, and 800 °C. The MPDs of the single cell with the La 9.5 Ge 5.5 Fe 0.5 O 26 electrolyte are superior to those of the SOFCs with apatite ceramics as electrolyte previously reported in the literature, thereby testifying to the potential of the La 9.5 Ge 5.5 Fe 0.5 O 26 ceramic as a promising electrolyte material for SOFCs. • Characteristics of Fe 3 + , Mn 3 + , Ni 2 + , and Ti 4 + doped La 9.5 Ge 6 O 26 ± δ were examined. • SOFC cells of NiO-SDC/La 9.5 Ge 5.5 Fe 0.5 O 26 /LSCF-SDC were built and characterized. • MPD of the cell with La 9.5 Ge 5.5 Fe 0.5 O 26 (0.39 mm) read 0.201 Wcm − 2 Wcm − 2 at 850 °C. • The results verified the potential of La 9.5 Ge 5.5 Fe 0.5 O 26 ceramic for use in SOFCs.

Molecular dynamics simulation of albite twinning and pericline twinning in low albite

Two twinning laws, the albite law and the pericline law, are the predominant growth twinning modes in triclinic plagioclase feldspars such as low albite, NaAlSi3O8, in which the aluminum and silicon atoms are in an ordered arrangement on the tetrahedral sites of the aluminosilicate framework. In the terminology used formally to describe deformation twinning in a triclinic lattice, these twin laws can be described as Type I and Type II twin laws, respectively, with the pericline twin law being conjugate to the albite twin law. In this study, twin boundaries have been constructed for low albite according to these two twinning laws and studied by molecular dynamics simulation. The results show that suitably constructed twin boundary models are quite stable for both albite twinning and pericline twinning during molecular dynamics simulation. The calculated twin boundary energy of an albite twin is significantly lower than that of a pericline twin, in accord with the experimental observation that albite twinning is the more commonly observed mode seen in plagioclase feldspars. The results of the molecular dynamics simulations also agree with conclusions from the prior work of Starkey that glide twinning in low albite is not favoured energetically.

Synthesis, characterization and crystal structures of nickel(II), palladium(II) and copper(II) complexes with 2-furaldehyde-4-phenylthiosemicarbazone

2-Furaldehyde-4-phenylthiosemicarbazone (HL) and its nickel(II), palladium(II) and copper(II) complexes: [Pd(L)2] (1), [Ni(L)2] (2), [Cu2(L)2(Et3N)2(H2O)4 ](SO4) (3), [Cu2(L)2(Et3N)2(H2O)4 ](NO3)2 (4), [Cu(L)2(H2O)2] (5), [Cu(L)(OAc)(H2O)] (6) were synthesized and characterized. The ligand has been characterized by elemental analyses, IR, electronic, 1H NMR and 13C NMR spectroscopy. The bidentate nature of the ligand is evident from the IR spectra.The nickel(II), palladium(II) and copper(II) complexes have been characterized by different physicochemical techniques like molar conductivity, magnetic susceptibility measurements, electronic, infrared and EPR spectral studies. For the copper(II) complexes metal–ligand bonding parameters have been evaluated from the EPR spectra. These parameters indicate the presence out-of-plane π bonding.In addition, the structures of the ligand, nickel(II) and palladium(II) complexes have been determined by single-crystal X-ray diffraction. These complexes crystallized into triclinic lattices with space group P1¯. The metal ion is coordinated through the sulfur atom and the azomethine nitrogen atom.

New zinc(II), palladium(II) and platinum(II) complexes of dl-piperidine-2-carboxylic acid; X-ray crystal structure of trans-[Zn2(μ-Ca)2(Hpa)2Cl6] and anticancer activity of some complexes

New complexes of dl-piperidine-2-carboxylic acid (dl-H2pa), [Zn(Hpa)(AcO)(H2O)2], trans-[Zn2(μ-Ca)2(Hpa)2Cl6], [M(bpy)(Hpa)]Cl and [M(pa)(PPh3)2] (M(II)=Pd, Pt) have been prepared and characterized on the basis of elemental analyses, molar conductivity and thermal measurements, IR, Raman, UV–Vis, NMR (1H and 31P) and mass spectroscopy. dl-Piperidine-2-carboxylic acids act as bidentate ligands, through the carboxyl oxygen and cyclic nitrogen atoms. The crystal structure of trans-[Zn2(μ-Ca)2(Hpa)2Cl6], obtained from the addition of ZnCl2 to dl-H2pa in either hard tap water or presence of CaCl2, has been determined by X-ray diffraction. It crystallizes in a triclinic lattice with space group symmetry P1. The complex has two zinc atoms in tetrahedral geometry, each ligated by a carboxyl oxygen and three chlorine atoms. The other carboxyl oxygen atoms from the two Hpa− ligands are bridged by two calcium atoms, i.e., there are two Zn(Hpa−)Cl3 units bridged by two calcium atoms. The free dl-H2pa and its complexes, trans-[Zn2(μ-Ca)2(Hpa)2Cl6], [Pd(bpy)(Hpa)]Cl and [M(pa)(PPh3)2] (M(II)=Pd, Pt) have been tested against the serous ovarian cancer ascites, OV 90 cell line.