共查询到20条相似文献,搜索用时 109 毫秒
1.
基于微分的思想,结合经典的双原子分子跃迁谱线表达式,提出了预言双原子分子P线系高激发振-转跃迁谱线的新解析物理公式.对于某分子电子体系的某一P支跃迁带,利用实验上获得的一组(15条)精确的跃迁谱线和该跃迁带对应的上下振动态的转动常数(Bυ',Bυ″)的精确数据,该公式不仅可以精确地重复已知的实验跃迁谱线,而且还能预测出实验上难以获得的更高激发态的跃迁谱线数据.利用该公式,研究了CO分子电子基态的(2,0)振-转跃迁带的<
关键词:
双原子分子
发射光谱
P线系')" href="#">P线系
CO 相似文献
2.
用多组态HFR方法系统地计算了高剥离类钠CrⅩⅣ-FmXC离子(Z=24~100)单电子组态的能级,相应谱线的跃迁波长,跃迁概率和振子强度.在已有实验的基础上,用自编的Fortran程序对HFR计算的3p2P1/2,3/2能级结果进行了最小二乘拟合计算.从而预测计算了CrⅩⅣ-FmXC离子3s2S1/2-3p2P1/2,3/2跃迁的谱线波长.计算结果与已有的实验值均符合得很好,尤其是与最近测量的实验值相当一致;而与其他理论预测值也基本吻合. 相似文献
3.
应用多组态Dirac-Fock(MCDF)方法,对Xe10+离子进行了理论计算,获得了跃迁波长和概率等数据.通过逐步引入4dn—5pn(n=1, 2, 3)电子相关的相互作用组态,重点研究了电子相关效应对4d8—4d75p跃迁系跃迁概率的影响.结果显示电子相关效应显著,表明了欲得到精确的4d8—4d75p的振子强度(跃迁概率)数据,理论计算中至少要包括到4d2—5p2的电子相关组态的影响.与实验测得的跃迁波长比较发现,理论结果与之有着较好的一致性;同时理论跃迁概率在两种规范下的结果符合得相当精确,显示了计算结果的可靠性.
关键词:
多组态Dirac-Fock(MCDF)方法
电子相关
跃迁概率 相似文献
4.
利用全相对论性多组态Dirac-Fock平均能级(MCDF-AL)方法系统地计算了高离化类铍离子自 旋禁戒2s2 1S0—2s2p3P1(Z= 10—103)跃迁的能级间隔和跃迁概率,计算中考虑了重要的核的有限体积效应,Breit修正 和QED修正,所得结果和最近的实验数据及理论计算值进行了比较,结果表明:高原子序数 的高荷电离子的自旋禁戒跃迁的跃迁概率和中性原子的电偶极E1的相当,在ICF和MC
关键词:
高离化态
跃迁概率 相似文献
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对SrAl12O19:Pr3+中4f2→4f2电偶极跃迁强度的参量化进行了研究.考虑明确的4f5d组态成分与4f2跃迁能级混杂对4f2组态内跃迁的影响.引入新的强度参数Tkq,参数值由3P0能级的相关实验数据拟合.利用拟合的参数T33和T53计算1S0向下各能级发射的跃迁强度,计算值与实验及Judd-Ofelt理论的结果进行了比较.
关键词:
12O19:Pr3+')" href="#">SrAl12O19:Pr3+
宇称态混杂
4f5d组态
强度参数 相似文献
9.
本文报道在300和77K对一组具有不同垒宽Lb0.23Ga0.77As双量子阱样品的光调制反射谱(PR)的研究结果。除观察到11H,11L和22H等容许跃迁外,同时还识别一个从Al0.23Ga0.77As价带顶至量子阱第一电子束缚能级的跃迁,另一个从量子阱第一轻空穴束缚能级至Al0.23Ga0.77As导带底的跃迁。利用这些跃迁确定导带边不连续性为0.63。对Lb关键词: 相似文献
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11.
Prabir K. Mukherjee 《Journal of Physics and Chemistry of Solids》2011,72(9):1066-1069
A model free energy has been constructed to describe the RIV-RIII rotator phase transition in alkanes in terms of the elastic strains and order parameter. The conditions for the RIV-RIII phase transition are discussed. From the free energy, the order parameter and the elastic strains are determined. The model free energy describes the first or second order character of the RIV-RIII transition depending on the strength of the coupling. The elastic properties in the vicinity of the RIV-RIII transition are discussed on the basis of a free energy expansion. The temperature dependence of the elastic constants is calculated on both sides of the transition. The coupling between the order parameter and elastic stains is shown to have a crucial influence on the phase behavior and the order of the transition. 相似文献
12.
R. Menegotto Costa L. Mendon?a Ferreira V. N. Vieira P. Pureur J. Schaf 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,58(2):107-113
We have studied experimentally the electrical magneto-conductivity near the
superconducting transition of YBa2Cu3O7-δ, YBa2
(Cu2.95Zn0.05)O7-δ and Y(Ba1.75Sr0.25)Cu3O7-δ polycrystalline samples. The measurements were performed in magnetic fields ranging from 0 to 400 Oe applied parallel to
the current orientation. The results show that the resistive transition of these systems proceeds in two stages. The pairing
transition occurs at the bulk critical temperature Tc, where superconductivity is stabilized within small and homogeneous regions of the
sample generically called grains. The regime of approach to the zero resistance state reveals the occurrence of a coherence
transition at a lower temperature Tc0. This transition is related to the connective nature of the granular samples and is controlled by fluctuations of the
order-parameter phase of individual grains. Our experiments show that the Zn-doping, besides depressing the pairing critical
temperature, strongly enlarges the temperature range dominated by effects related to the coherence transition. The substitution
of Ba by Sr causes only a small reduction of Tc, but also enhances significantly the effects related to the grain
coupling phenomenology. In general, our results indicate that these impurity substitutions in YBa2Cu3O7-δ produce or magnify the granularity at a microscopic level, enhancing the effects of phase fluctuations in the conductivity
near the transition. 相似文献
13.
Determination of the magnetocaloric effect associated with martensitic transition in Ni46Cu4Mn38Sn12 and Ni50CoMn34In15 Heusler alloys
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This paper presents a study of the inverse magnetocaloric effect (MCE) corresponding to martensitic transition using various experimental approaches for Ni46Cu4Mn38Sn12 and Ni50CoMn34In15 Heusler alloy. Through heat capacity measurements,it is found that the "giant inverse MCE" upon martensitic transition evaluated by the Maxwell relation in these alloys are unphysical results. This is due to the coexistence of both martensitic and austenitic phases,as well as thermal hysteresis during martensitic transition. However,careful study indicates that the spurious results during martensitic transition can be removed using a Clausius-Clapeyron equation based on magnetization measurements. 相似文献
14.
Cr-doped manganites Sr0.9Ce0.1Mn1−yCryO3 (y=0, 0.05, and 0.10) have been systematically investigated by X-ray, magnetic, transport, and elastic properties measurements. For parent compound Sr0.9Ce0.1MnO3, it undergoes a metal-insulator (M-I) transition at 318 K, which is suggested to originate from a first-order structural transition accompanied by Jahn-Teller (JT) transition. With increasing Cr doping content, the JT transition temperature decreases. The Cr doping suppresses the antiferromagnetic (AFM) state and makes the system spin-glass (SG) behavior at low temperatures. In the vicinity of JT transition temperatures, the softening of Young's modulus originating from the coupling of the orbital (quadrupolar) moment of the eg orbital of Mn3+ ion to the elastic strain has been observed. The anomalous Young's modulus properties imply the electron-phonon coupling due to the JT effect may play an important role in the system. 相似文献
15.
A phase transition has been discovered in Cd2Ta2O7 near 200 K which is about the same temperature at which Cd2Nb2O7 is known to become ferroelectric. However, Cd2Ta2O7 does not become ferroelectric below this transition. The nature of this transition was also studied in the Cd2Nb2?xTaxO7 series using low temperature X-ray, SHG, and DSC techniques. 相似文献
16.
Ryo EndohNobuhiro Matsumoto Junji AwakaShuji Ebisu Shoichi Nagata 《Journal of Physics and Chemistry of Solids》2002,63(4):669-674
A normal thiospinel CuIr2S4 exhibits a temperature-induced metal-insulator (M-I) transition around 230 K with structural transformation, showing hysteresis on heating and cooling. On the other hand, CuCr2S4 has the same normal spinel structure without the structural transformation. CuCr2S4 has been found to be metallic and ferromagnetic with the Curie temperature Tc~377 K. In order to see the effect of substituting Cr for Ir on the M-I transition, we have carried out a systematic experimental study of electrical and magnetic properties of Cu(Ir1−xCrx)2S4. The M-I transition temperature shifts to lower temperature with increasing Cr-concentration x and this transition is not detected above x~0.05. The ferromagnetic transition temperature decreases as x is decreased and the transition does not occur below x~0.20. 相似文献
17.
Rolf Willestofte Berg Steen Skaarup 《Journal of Physics and Chemistry of Solids》1978,39(11):1193-1196
The known phase transition in (CH3)4N NiCl3, at 171 K, has been characterised by far IR spectroscopy. The transition is explained as due to a formation of weak labile C-H,…, Cl hydrogen bonds at low temperatures, restricting the “free” internal rotations of the methyl groups and perhaps at the same time ordering the orientations of the tetramethylammonium ions. No similar transition in (CH3)4N NiBr3 was found. 相似文献
18.
A. Levstik R. Blinc P. Kadaba S. Čižikov I. Levstik C. Filipič 《Solid State Communications》1975,16(12):1339-1341
Orthorhombic CsH2PO4 undergoes a ferroelectric transition at Tc = ?119.5°C, whereas the ferroelectric transition temperature in isomorphous CsD2PO4 is Tc = ?5.55°C. The transitions are of first order in both cases. The rather large isotope effect demonstrates the importance of the OHO bonds in the transition mechanism. 相似文献
19.
Yoshiyuki Yoshida Kotaro Iwata Naofumi Aso 《Journal of Physics and Chemistry of Solids》2011,72(5):559-561
We have measured magnetization curves and powder neutron diffraction of double-layered Ruddlesden-Popper type ruthenate Sr3−xCaxRu2O7 (x=1.5, 2.0 and 3.0). The field dependence of the magnetization revealed that the transition field of metamagnetic transition along the b-axis shifted to lower fields and that the transition became broad with increasing Sr content. The slope of the magnetization curve also increased with increasing Sr content below the metamagnetic transition. These results indicate that an itinerant component is partly introduced by the Sr substitution. From the magnetic reflection, on cooling below TN, an additional reflection was observed at (0 0 1) for each x, and the amplitude increased with decreasing temperature. The observed diffraction patterns are very similar to those of Ca3Ru2O7. We conclude that the magnetic structure of the antiferromagnetic ordered phase is basically the same structure with that of Ca3Ru2O7. 相似文献