Spectra Of Bound Excited States Of Sm Atom

Study of microscopic world mainly relies on spectroscopic techniques; inorder to obtain the electron spectroscopy, molecular vibrational or rotationalspectroscopy of atomic or molecular, even get its structures and associatedinformation. The spectral method which is currently used mainly based on theabsorption and scattering principle. For example:both ionization spectroscopyand fluorescence spectroscopy are particles first absorb photon and thenionization or emit fluorescence; Raman spectroscopy reflect the molecularvibration characteristics threw the inelastic scattering principle. The study ofrare earth samarium electronic structure through ionization spectroscopy andthe study of vibration characteristics of the organic molecules in aqueoussolution by Raman spectroscopy will introduce respectively by this paper, inorder to obtain its microscopic information.Studies of highly excited states of atoms may provide important information aboutatoms, such as the interaction between light and matter, the structure or dynamics ofatoms. Thus, they have extensive application values in the new lasers, laser isotopeseparation, inertial confinement fusion, and other high-tech areas. Development ofhighly excited states of atoms has very important significance for spectroscopy,atomic physics, astrophysics and quantum mechanics. Rare-earth elements have manychemical properties and spectral characteristics，making them the strategic elementsworldwide in twenty-first century. The Sm element is one of typical heavy rare-earthelements, having a very complex atomic structure and special physical and chemicalproperties.The spectra of odd-parity bound excited states of Sm atom were studied with acombination of multistep resonant laser excitation and photoionization detection orelectric field ionization detection.In order to uniquely determine the total angular momentum of a bound excitedstate of Sm atom, the experiment designs three different excitation paths. By selectingdifferent initial and final states for the transitions, the Sm atom excited by threedifferent excitation paths may reach the same energy region. In the three excitationpaths, the wavelength of the first dye laser can be fixed at different values so that Smatom can be excited from different initial states to three different atomic states withthe4f66s6p electron configuration, and wavelength of the second laser can be fixed atdifferent values so that the Sm atom will be further excited to three different atomicstates with the4f66s7s electron configuration; Finally, the Sm atom will be furtherexcited to a series of odd parity states to be measured by controlling the wavelength ofthe third laser in a given region. The Sm atom in these states can be excited further toa continuum state by absorbing a photon with a wavelength3, thereby can bedetected with the photoionization. Obviously, the three spectra obtained with differentexcitation paths in the same energy region have the same parity. However，eachspectrum has three different angular momenta. Comparison of the three spectra willuniquely determine the total angular momentum of each highly excited state according to the selection rules.With these three excitation paths, having not reported before, lots of newspectroscopic data of bound excited state with different parities or angular momentumvalues can be obtained in the same energy region, which will enrich the spectralinformation of Sm atom significantly. A large number of new bound states areobserved in this experiment for the first time, while the energy levels of a few boundstates reported earlier are verified. Comparison of spectra obtained with differentexcitation paths, not only the total angular momentum of a new atomic state can bedesignated, but also the information of line strengths of the transitions can beclassified into three grades: strong (S), middle(M) and weak (W), according to theintensity of signal. The above information of bound excited states of the Sm atom willenrich the spectral data, test the new theory and play an important role in other fields.Apart from the photoionization detection method, the electric field ionizationdetection is also used on highly excited states of Sm atom. However, no new resultsmay be found around the first ionization limit with this detection method, although thestrongest electric field of this laboratory,2000V/cm, is applied to the plates.Although the same method and experimental parameters are verified for the Eu atom,they are no t suitable for the Sm atom, the reasons of which need to be further studied.In order to study the vibration spectrum and characteristics of microscopicparticle, the Raman spectra of some molecules and their properties are also studied inthis paper. Therefore, Raman spectra of some organic materials are measured andanalyzed with a Raman spectrometer，which provide the information about the Ramandisplacement and property of molecules in the materialed with the Raman scatteringdetection. The results not only allow us to compare their characteristic and differencebut also give us a better understanding about elastic and inelastic collisions.