Electron, atom ratio excess compound

In the case of EC, the daughter atom is considered as an impurity atom in the chemical compound of the parent atom and its chemical state is different both from that in ordinary chemical compounds of parent element and from that of daughter element. In addition, the outer-shell electron configuration of the parent atom is preserved after EC and the daughter atom has an excess electron in the outer shell in comparison with the PI case. These facts indicate that in order to compare the K/ / Ca ratios by PI with those by EC, the difference in the chemical surroundings should be taken into consideration as well as the difference in the number of electrons in the atom. 

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