Ionization Energies Of Noble Gases

Redbelly98

Okay, that is a puzzling image. But I have found an explanation in the page where that image is posted:

http://www.crystalmaker.com/support/...dii/index.html

There is a lot of information there, about different ways that "atomic radii" can be defined. Scroll down to the "Table of Atomic Radii" on that page, which lists radii for several different definitions of that term. Under most definitions, noble gases have the smallest radius in their respective row of the periodic table. Only for the "van der Waals radius" is the noble gas radius larger as shown in your figure. I'm a little puzzled as to why they chose that one to use in their chart at the very top of their page, but they did.

Most importantly, look at the definitions of radii that use either (1) an isolated atom, or (2) an atom covalently bonded to another atom -- for these definitions, the noble gases are the smallest in their respective rows.

chikis

from the link you pasted in, I saw that after calculating Z_eff for Na cation or F anion and neutral Ne, the aticle stated it clearly that Na cation has the highest Z_eff and thus the smallest atomic radius.
But we are not talking about cation or anions here.

chikis

You are correct. Am begining to come to my senses. Initialy whenever the word radi is mentioned, what comes to my mind is nothing but atomic radi. I never knew there are diffrences. I used to think that ionic, vandawal, atomic and convalent radi are all the same. But in this thread am discussing atomic radi. All the same, I say thank you for the awareness.
I now accept that atomic radi decreases left to right across a period thus the nobles gases being at the extrem right of each row should have the smallest atomic radi.