The document covers selective topics in nuclear chemistry, including nuclear isomerism, internal conversion, and the Auger effect. It explains that nuclear isomers are metastable states with relatively long half-lives, and discusses the mechanisms by which nuclei transition to ground states, including the ejection of electrons. The Auger effect is described as the process where the filling of an inner-shell vacancy leads to the emission of an electron from the same atom.

1. NUCLEAR CHEMISTRY (Selective topics)
By ESWARAN.M
SRMV CAS
(17PCH003)
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2. OUTLINE
 NUCLEAR ISOMERISM
 INTERNAL CONVERSION
 AUGAR EFFECT
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3. NUCLEAR
ISOMERISM
A NUCLEAR ISOMER IS A METASTABLE STATE OF AN ATOMIC NUCLEUS
CAUSED BY THE EXCITATION OF ONE OR MORE OF ITS NUCLEONS (PROTONS
OR NEUTRONS). "
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4. "Metastable" refers to the property of these nuclei whose excited states
have half-lives longer than 100 to 1000 times the half-lives of the excited nuclear
states that decay with a "prompt" half life (ordinarily on the order of 10−12 seconds).
As a result, the term "metastable" is usually restricted to isomers with half-lives of
10−9 seconds or longer.
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5. ISOMER TRANSITON 5

6. INTERNAL CONVERSION
 The transition of a nucleus from an excited to the ground state may occur by
the EJECTION OF ORBITAL ELECTRONS
 It is an alternative GAMMA  emission
 IF the energy TRANSFERRED to the electrons in this process exceeds the
electron binding energy EB ,The electron is ejected with a kinetic ENERGY
 Ee =E - EB
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7. AUGER EFFECT
 The Auger effect is a physical phenomenon in which the filling of an inner-
shell vacancy of an atom is accompanied by the emission of an electron from
the same atom. When a core electron is removed, leaving a vacancy, an
electron from a higher energy level may fall into the vacancy, resulting in a
release of energy.
 The Auger electron is generated during an excited atoms relaxation process,
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8. THANK YOU
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