Ground-state term, atomic

The term symbol summarizes the properties of any state and also permits a concise representation of spectral transitions. It consists of an upper case letter (S, P, D. ..) to represent the net orbital angular momentum (L) and a number written as a superscript on the upper left to indicate spin multiplicity (i. e. the number of possible orientations of total spin of the atom). L is zero for Fe " (no angular momentum) and 2 for Fe ". The spin multiplicity is defined as (2S -i- 1) S = 5/2 and 2 for Fe " and Fe ", respectively. The ground state term symbol for Fe " is, therefore, 85 2 and for Fe " it is 04. The subscript on the right is the value J. 

Determine all of the term symbols for the following free atoms. Choose the ground state term in each case. 

More recently Men33 has proposed that electronegativity be defined in terms of the average one-electron energy of valence shell electrons in ground-state free atoms which may be obtained spectroscopically. This quantity is termed the configuration energy ... 

Figure 5.3 Correlation diagram of molecular terms for a pair of similar (excited and ground-state) alkali atoms. The right part of the figure corresponds to free atoms, the left part corresponds to the strong dipole-dipole interaction (Fdip A ). Dots mark crossings of terms coupled by the Coriolis interactions.

From the theoretical point of view, the electrophilicity concept has been recently discussed in terms of global reactivity indexes defined for the ground states of atoms and molecules by Roy et al.18 19. In the context of the conceptual density functional theory (DFT), a global electrophilicity index defined in terms of the electronic chemical potential and the global hardness was proposed by Maynard et al.20 in their study of reactivity of the HIV-1 nucleocapsid protein p7 zinc finger domains. Recently, Parr, Szentp ly and Liu proposed a formal derivation of the electrophilicity, co, from a second-order energy expression developed in terms of the variation in the number of electrons.21... 

A theoretical expression of the hyperfine structure of the ground state of atomic hydrogen is given in eqn (1) below. Despite the high experimental accuracy of frequency measurement, values of the hydrogen ground state hyperfine structure are principally limited in accuracy at the ppm level by incomplete knowledge of the structure of the finitely-sized proton, represented in eqn. (1) by one term in a sum of various corrections ei [17]. 

The excitation transfer of an atom with like atoms (Case 1) can affect the spectrum. If either an upper or a lower state is connected to the ground state by optically allowed transitions and these excited atoms are surrounded by ground state like-atoms, the Lorentzian spectrum half-line width (w) of the transition is expressed in terms of k (1, 5) as... 

With one exception, the situation is analogous to that for the desorption of a true ion. The polarization energy did not enter in Eq. (48) it has the same value at the Schottky saddle as at the equilibrium position xe and therefore cancels. Now the ground state is atomic, and the effect of the field must therefore be represented as a polarization term F2 (a0 - a+). Evaporation at T ----- 0 will occur when the field satisfies the condition... 

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