Hydrogen term symbol

Term Symbols, plicity of an atom by a symbolic representation. For example, for the hydrogen atom... 

We have seen that the term symbol for the ground state of the hydrogen atom is -5i/i. For a helium atom t = 0, 5 = 0. J = 0, and the term symbol for the ground state is 5 . For an atom such as boron, we can make use of the fact that all closed shells and subshells (such as the He example just given) contribute nothing to the term symbol. Hence both the Is- and 2jZ electrons give L = S = J = 0. The 2p electron has L = I, 5 = J. and J = 1 i, yielding -Pyz carbon there are two p electrons. 

Atomic lithium has the electronic configuration 1/2, and its term symbol is the same as that for hydrogen. Similarly, the term symbol for beryllium 2 ) is the same as that for helium, 5q. 

Radial Dirac Equation for Hydrogen-Like Atoms 215 Table 6.3 Quantum numbers sorted by shells and assigned to shell and term symbols. 

If the molecular ion BH has the ground MO configuration (la ) (2a ) (le ), what is its ground state term symbol The molecule is planar, and all three hydrogens are equivalent. 

EXAMPLE 5-5 For a hydrogen atom having n = 3,1 = 2, what are the possible j values, and how many states are possible Indicate the lengths of the j vectors in a.u. What term symbols apply ... 

Give all the allowed term symbols for a hydrogen atom (a) in the = 1 level, (b) in the = 2 level. In each case, total up the states to see whether you have tlie expected number. 

Show that the maximum multiplicity term symbols for half-filled subshells will always have an S (that is, L = 0) term symbol. Do this by considering that L can also be determined from the sum of the values for the rrt( quantum numbers of the electrons in the hydrogen-like orbitals. 

Give the term symbol or symbols for each of the excited electron configurations of the hydrogen molecule ... 

Lowest energy levels of the hydrogen atom (horizontal lines) and the allowed transitions. States with the same term symbol have been placed in the same column for clarity. 

This result helps us to understand the symbol pH, first defined by a Danish chemist, Sorenson. He used the p to stand for the Danish word poienz (power) and H to stand for hydrogen. After a change of sign, pH is the power of ten needed to express the hydrogen ion concentration in moles per liter. In acidic solutions, pH is less than 7 (pH < 7) and in basic solutions, pH is greater than 7 (pH > 7). Table 11-111 expresses the results of Table 11-11 in terms of pH. 

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