Containing Phosphine Organic-inorganic Hybrid Molecule Synthesis,phase Transition And Nonlinear Optical Properties Research

Phase transition materials(PTM)have been widely hotspot in current research because of their excellent properties such as information storage,photoelectric sensing,and energy transformation.However,organic-inorganic hybrid materials hold both organic and inorganic components.The organic component has structural modifiability,easy processing,and polarity merits,otherwise the inorganic component can provide semiconductor properties,photoluminescence properties,and magnetic properties.The organic component is susceptible to the influence of the external environment(temperature,electric field,light),and can be arranged disorderly to cause changes in the dipole moment,resulting in structural phase transition.In general,there will be obvious dielectric anomaly near the phase transition temperature,accompanied by optical and electrical properties,which provides a way to explore phase transition materials.Therefore,in order to get a novel phase transition material,we pick the triphenyl phosphine oxide(TPPO)compounds with inorganic strong acid,such as sulfuric acid,deuterosulfuric acid,selenic acid)and a class of tetrahedral configuration acid synthesis a series of new type organic inorganic hybrid compound.And organic inorganic hybrid compounds were synthesized by using the tricyclohexylphosphine oxides(TCPO)and a class of tetrahedral configuration acid,analysing the crystal structure,phase transition,dielectric properties,and nonlinear optical properties.In the first part,[(TPPO-H)₂SO₄](1),[(TPPO-D)₂SO₄](2),[(TPPO-H)₂Se O₄](3)was synthesized by using triphenylphosphine oxide(TPPO)and sulfuric acid,deuterium sulfuric acid and selenic acid aqueous solution in acetone solution and methanol at a stoichiometric molar ratio of 2:1.The results of differential scanning calorimetry(DSC)showed that compound 1 had a pair of reversible phase transitions at temperature of 419 K and 312 K.It was further confirmed by the variable temperature single crystal apparatus that the reversible phase transition was caused by the competition between the length of the donor acceptor hydrogen bond formed by the protonated oxygen atom in triphenylphosphine oxide and the oxygen atom in the sulfate anion at room temperature and high temperature.In addition,Compound 1 exhibited a reversible step type the dielectric spectrum.The large thermal hysteresis peak indicates the first order phase transformation.Besides the SHG signal strength of the second order nonlinear optical response is twice stronger than KDP,which can be used as a potential switchable nonlinear material.In the second part,three crystals[C₃₆H₃₀O₂P₂HCl O₄](4),[C₃₆H₂₉O₂P₂HBF₄](5)and[C₃₆H₃₀O₂P₂HPF₆](6)were synthesized with triphenylphosphine oxide(TPPO)compound as substrate and perchloric acid,tetrafluoroboric acid and hexafluorophosphoric acid at a stoichiometric molar ratio of 2:1,respectively.The crystal structure,phase transition properties,dielectric properties,and optical properties of compounds 4,5 and 6 were researched by X-ray single crystal diffraction,differential scanning calorimetry,dielectric apparatus and second order nonlinear optical frequency doubling measuring instrument.However,compound 4,5,6 was not detected to reversible phase transition and dielectric anomaly by differential scanning calorimetry and permittivity measurement at variable temperature,but compound 5 had a strong SHG signal response.In the third part,two crystals[TCPOHCl O₄](7),[TCPOHRe O₄](8)were synthesized by using tricyclohexylphosphine oxide(TCPO)compound with perchloric acid and perrhenic acid at a stoichiometric molar ratio of 1:1,respectively.According to the relevant test results,compound 7 had no reversible phase transition and dielectric anomaly,while compound 8 had reversible phase transition,but no reversible abnormality was detected in the dielectric measurement...