Lithium Hydrogen Isotope Compound Nature Of Theories And Their Films

The aim of ICF is to generate a condition known as "ignition". To achieve the condition, the fuel must be heated to high temperature and kept at high pressure for a long-enough time for initiating fusion. The density (p) and radius(R) of fuel after compression must meet the conditions of pR>0.3g/cm2. A large initial density of gas fuel and thus an extremely high pressure at room temperature in a single-shell capsule usually make the capsule broken. Therefore, cryogenic targets are largely applied in the inertial confinement fusion now. In the cryogenic targets, the common fusion fuel is DT ice plus with DT gas in the centre of the target. The thickness of the DT ice usually is 80 to 100 microns with the density of 0.25g/cm3 and the surface roughness (Rq) below one micron. As the DT gas or ice can't supply tritium by themselves, the main source of tritium complement is the external one. Increasing the fuel capacity by augmenting the thickness of DT ice may affect ignition because the surface roughness of DT ice increases with the thickness. As a fusion fuel, the tritium from the reaction between the isotopes 6Li,7Li in LiDxT1-x and neutrons can take part in the fusion reaction or recycling. The isotope 6Li,7Li may also slow fast neutrons to diminish the activation of neutrons. Moreover LiDxT1-x has a high DT density. When x=0.25 and 0.5, the density of DT in LiDxT1-x is equal to that of DT ice. The property can increase reserves of fuel and combustion time without increasing the volume or charging the inflation pressure of ignition targets. If the design of targets is reasonable, it can use 6Li and 7Li to generate tritium. The ideal mentioned above is likely to break through the top filling of DT fuel in cryogenic targets, which will settle the fuel of self-sustaining problem.On the other hand, the energy created by plasma in ICF mostly centralizes in soft x-ray region (0.1-1.5KeV). The research on laser plasma in ICF is very important, because it is directly correlative with the implosion of the target pellets. The soft x-ray multilayer mirrors are perfect optical element to study soft x-ray spectrum transmitted by laser-target plasma. At present the soft x-ray multilayer holding high reflectivity has been manufactured in 10nm<λ<20nm region, but in 20nm<λ<30nm region the research on soft x-ray multilayer holding high reflectivity have still been search stage. The isotopic compound of lithium hydride's absorption coefficient in the soft x-ray region is small and therefore an ideal candidate as a spacer layer in multilayer mirrors. In conclusion, the research on thin films of isotopic compound of lithium hydride as the fusion fuel in ICF and spacer layer in soft x-ray multilayer mirrors takes on significant scientific meaning and application value.Though isotopic compound of lithium hydride as the fusion fuel in ICF and spacer layer in soft x-ray multilayer mirrors takes on significant application background, many problems such as it's structure, density, hydrolysis and film's surface roughness in preparation must be settle for fully utilizing it's excellent property. This paper has studied crystal structure, density, thermodynamics and optical properties of isotopic compound of lithium hydride, dynamics between isotopic compound of lithium hydride and water and preparation technology of films. These results corresponded with other people's experimental and theoretic results and obtained some results which weren't report. These results aren't only helpful to understand properties of isotopic compound of lithium hydride, but also establish experimental and theoretic basis for applying isotopic compound of lithium hydride in ICF. The main contents include:(1) All calculations presented in this work were performed with CASTEP code in MS4.0 based on density function theory. We constructed the structures of LiHxD1-x, LiHxT1-x, LiDxT1-x(x=0,0.25,0.5,0.75,1.0) and then optimized the geometrical structures of the crystal at different values of x with the density functional theory method within the generalized gradient approximation (GGA).The lattice constants and the density of LiH, LiD and LiT was calculated. The results were in good agreement with other people's experimental and theoretic results. It was first to obtain the lattice constants and the density of LiHxD1-x, LiHxT1-xand LiDxT1-x(x=0,0.25,0.5,0.75). The results showed that the density of DT in LiD0.5T0.5 and LiD0.25T0.75 is equal to that of DT ice. The idea showed LiDxT1-x could increase the fusion fuel capacity and extend combustion time without increasing the volume or charging the inflation pressure of ignition targets, which is a crucial guidance for developing the new-style fusion fuel.(2) Some thermodynamic properties at different temperature for LiH, LiD and LiT were calculated by B3LYP density function method in Gaussian 03 software. The vibration energy, vibration entropy and thermodynamic functions for LiH, LiD and LiT were studied by the quasi-harmonic debye model. The results showed that Li absorbing hydrogen isotopes were radiative and decreasing entropy processes. At the same temperature, the relation of dissociation pressure between hydrogen, deuterium and tritium is P(H2)< P(D2)