The Theoretical Research On Diatomic Molecules NO、N₂ And O₂ Radiation Characteristics Of High Temperature

This thesis iscomposed in four parts. The first part is introduction,it mainly introduced research contents and significance in theoretical and practical. The second part recounted the fundamental theory of principle and calculation method which include potential energy function, spectrum constant and vibration energy level. The third part mainly demonstrated the calculation results in potential energy function,spectrum constant and vibration energy level,meanwhile comparing with the experimental value and RKR potential. The fourth part introduced the calculation principle of partition function and line intensity at hightemperature, calculatingand analysising these moleculesand listing the calculationresults furtherly.Accurate diatomic molecular of potential energy function are able to obtain the molecular structure,energy and spectrum properties. It’s the foundation of atomic molecular physics, physical chemistry and microcosmic reaction kinetics.This thesisused the Gaussian quantum chemistry program,chose the methodsin high precision of CCSD(T)/6-311++G(3d2f),QCISD/cc-pvtz and CCSD(T)/6-311++G(3df,3pd) to optimize and potential scan NO,N2 and O2 molecules energy in the ground state, the results of theoretical calculation suited well with the experimental values. Then use the Rydberg-Klein-Rees(RKR) backstepping technique to test potential curve,The RKR potential and potential energy curve can coincidence in the range of low energy well.Calculate the nuclear radial movement Schr?dinger equation furtherly. Got vibration level,the rotational inertia constants and centrifugal distortion constants when J ?0 vibration dynamic,a large amount of data was firstly reported in this thesis.With the rising status of frontier science in gas molecules of astrophysics and atmospheric physics, gas molecule optical properties receive much concern under the condition of extreme high temperature. However,molecular spectroscopy mainly studied energy level structure or line position,at present,the study of spectral intensity is relatively less,because it is very difficult to measure the molecular spectral line intensity accurately at indoor temperature. According to the HITRAN database provided NO,N2 and O2 molecules line strength in(X2/3)1-(X2/3)0,1-0 and X1-X0 transition,using high temperature distribution function and line strength formula,make transition dipole moment squared 2R?as a constant. Expend the temperature to 4000 K and 5000 K,calculation of high temperature transition wave are between 1686cm-1-1993cm-1, 1992cm-1-2625cm-1 and 1368cm-1-1715cm-1 in the transition of spectral line intensity and draw the high temperature simulated spectra as well.