Group 15 element ionization potential

Symbol Cd atomic number 48 atomic weight 112.41 a Group IIB (Group 12) metallic element ionization potential 8.994eV electron configuration [Kr]4di°5s2 valence state +2 standard electrode potential, E° -0.40V. The isotopes and their natural relative abundance are ... 

In general, ionization potential decreases while going down the group. Therefore, ionization potential of the elments of second transition series have lower values than those of the elements of first transition series as expected. However, ionization potentials of the elements of third transition series except lanthanum have higher values of ionization potentials due to lanthanide contraction. The atomic radii of the elements of second and third transition series are almost same but atomic numbers differ by 32. Thus, the outer electrons are firmly attached to the nucleus and ionization potential values are very hi. On accoimt of this, the elements of third transition series are almost inert under ordinary conditions. 

Table 4.2 Nonrelativistic (NR) and relativistic (R) ionization potentials A p and electron affinities AEp (positive values and in eV), relativistic effects Ap and relativistic enhancement factors y for the Group 11 elements of the periodic table.

Figure 4.5 Nonrelativistic (NR) and relativistic (R) ionization potentials and electron affinities of the group 11 elements. Experimental (Cu, Ag and Au) and coupled cluster data (Rg) are from Refs. [4, 91, 92].

The choice of the fill material initiating the discharge is very important. Together with a standard mercury fill it is often desirable to incorporate an additive in the fill material that has a low ionization potential [38, 39]. One category of low-ioniza-tion-potential materials is the group of alkali metals or their halides (Lil, Nal) but some other elements, such as Al, Ga, In, T1 [40, 41], Be, Mg, Ca, Sr, La, Pr, or Nd [23, 37, 42], can be used. 

The group IA elements have the lowest ionization potentials of any atoms in their respective periods. As you probably already know, these atoms have a single electron that resides in a shell outside of other shells that are filled. 

Hg+1 or Tl+1) however, this effect does not seem to be particularly operative in Group IV, since the 3rd ionization potentials are similar for the elements Si through Pb. 

We define here Wlh and W2h theories, respectively, as the modifications of Wl theory for which AVnZ basis sets are only used on elements of groups V, VI, VII, and VIII, but regular VnZ basis sets on groups I, II, III, and IV. (The h stands for heteroatom , as we originally investigated this for organic molecules.) For the purpose of the present paper, we have repeated the validation calculations described in the previous section for Wlh and W2h theories. (For about half of the systems, Wl and Wlh are trivially equivalent.) Some representative results can be found in Table 2.1 for atomization energies/heats of formation, and in Table 2.2 for ionization potentials and electron affinities. 

A number of useful properties of the Group 1 elements (alkali metals) are given in Table 8. They include ionization potentials and electron affinities Pauling, Allred-Rochow and Allen electronegativities ionic, covalent and van der Waals radii v steric parameters and polarizabilities. It should be noted that the ionic radii, ri, are a linear function of the molar volumes, Vm, and the a values. If they are used as parameters, they cannot distinguish between polarizability and ionic size. 

Symbol Ba atomic number 56 atomic weight 137.327 a Group llA (Group 2) alkaline earth element electronic configuration [Xejs valence state +2 ionic radius of Ba2+ in crystal (corresponding to coordination number 8) 1.42 A first ionization potential lO.OOeV stable isotopes and their percent abundances Ba-138 (71.70), Ba-137 (11.23), Ba-136 (7.85), Ba-135 (6.59), Ba-134 (2.42) minor isotopes Ba-130 (0.106) and Ba-132 (0.101) also twenty-two radioisotopes are known. 

Symbol Be atomic number 4 atomic weight 9.012 a Group IIA (Group 2) metal the lightest alkaline-earth metallic element atomic radius l.OOA ionic radius (Be2+) 0.30A electronic configuration Is22s2 ionization potential, Be 9.32eV, Be + 18.21 eV oxidation state +2... 

Symbol Cs atomic number 55 atomic weight 132.905 a Group lA (Group 1) alkali metal element electron configuration [Xe]6si atomic radius 2.65 A ionic radius (Cs ) 1.84 A ionization potential 3.89 eV valence +1 natural isotope Cs-133 37 artificial isotopes ranging in mass numbers from 112 to 148 and half-lives 17 microseconds (Cs-113) to 2.3x10 years (Cs-135). 

Symbol Kr atomic number 36 atomic weight 83.80 a Group 0 (Group 18) element inert gas element electron configuration Is22s22p63s23p 3di°4s24p valence state 0 an uncommon valence state +2 exists for its difluoride first ionization potential 13.999 volt six stable natural isotopes are known most abundant isotope Kr-84. Natural isotopes and their abundances Kr-78 (0.354%), Kr-80 (2.20%), Kr-82 (11.56%), Kr-83 (11.55%), Kr-84 (56.90%), Kr-86 (17.37%). 

Symbol Nd atomic number 60 atomic weight 144.24 a rare earth lanthanide element a hght rare earth metal of cerium group an inner transition metal characterized by partially filled 4/ subshell electron configuration [Xe]4/35di6s2 most common valence state -i-3 other oxidation state +2 standard electrode potential, Nd + -i- 3e -2.323 V atomic radius 1.821 A (for CN 12) ionic radius, Nd + 0.995A atomic volume 20.60 cc/mol ionization potential 6.31 eV seven stable isotopes Nd-142 (27.13%), Nd-143 (12.20%), Nd-144 (23.87%), Nd-145 (8.29%), Nd-146 (17.18%), Nd-148 (5.72%), Nd-150 (5.60%) twenty-three radioisotopes are known in the mass range 127-141, 147, 149, 151-156. 

Symbol Rb atomic number 37 atomic weight 85.468 a Group I (Group 1) alkali metal element electron configuration [Kr] 5si valence -i-l atomic radius 2.43A ionic radius, Rb+ 1.48A atomic volume 55.9 cc/g-atom at 20°C ionization potential 4.177 V standard electrode potential Rb+ + e Rb, E° = -2.98V two naturally-occurring isotopes, Rb-85 (72.165%) and Rb-87 (27.835%) Rb-87 radioactive, a beta emitter with a half-bfe 4.88xl0i° year twenty-seven artificial radioactive isotopes in the mass range 74—84, 86, 88-102. 

Symbol Na atomic number 11 atomic weight 22.9898 a Group lA (Group 1) alkali metal element electron configuration [NejSs valence +1 atomic radius 1.85A ionic radius, Na" in crystals 1.02A (for a coordination number 6) ionization potential 5.139 eV standard electrode potential, E°(Na+ + e Na) -2.71 V one naturally-occurring stable isotope, Na-23 (100%) sixteen artificial radioactive isotopes in the mass range 19-22, 24—35 longest-lived radioisotope, Na-22, ti/2 2.605 year shortest-lived isotope Na-35, ti/2 1.5 ms. 

Group IIB elements bond energies of, 11 316 heats of atomization, 11 313 ionization potentials, 11 310, 311 valence state promotion energies, 11 311, 312... 

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