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Symmetry Of The Periodic Table
JERIES A. RIHANI |
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Page 1 - Symmetry: Original Untrimmed Version Page 2 - Symmetry: Trimmed Version With Orientation & Spin Page 3 - Modern Periodic Table: Long Form Page 4 - Modern Periodic Table: Standard Form Page 5 - Modern Periodic Table: Separated Form Page 6 - Physicist's Periodic Table WebElements - Mark Winter (University Of Sheffield) ACS - Periodic Table Atomic Orbitals - Periodic Table Atomic Spectra - Periodic Table Chemogenesis - Mark Leach The Extended Periodic Table - Web Ring
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"Relativistic Effects in Limiting The Atomic Number of Superheavy Elements" The above title is that of a paper by Dr. F.W. Giacobbe recently published in the Electronic Journal of Theoretical Physics(www.ejtp.com). In this paper (No.1,2004) the author proposes a "method of estimating the maximum possible atomic number (i.e., Z value) that can be possessed by relatively stable superheavy elements (SHEs). This method is based upon the supposition that no electron orbiting a SHE atomic nucleus can have a speed equal to, or greater than, 0.92c (where c is the speed of light) without significantly increasing the probability of electron capture (i.e., inverse beta decay) by that atomic nucleus. According to this supposition and a relatively simple calculation based upon a two particle Bohr atom model, no stable naturally occurring, or synthetic, chemical elements can exist with atomic numbers greater than 125. This conclusion does not place any limitations on potential nuclear Z values of any possible SHE nucleus. However, it does suggest that stable combinations of SHE nuclei, having Z values greater than 125, and electrons, are unlikely." Abstract, Dr. F.W. Giacobbe, www.ejtp.com, No.1,2004. This paper was brought to my attention in an e-mail attachment, on June 24, 2004, by my colleague Wolfram Klehr of Apsidium. I replied with the following slightly modified and revised comment: "No doubt, this paper represents a very important development. However, I beleive if the author takes into account the concept of symmetry of the periodic table, as an additional limiting factor, with the rest of the limiting relativistic effects and approximations he has considered, he may find that Z for atoms (not nuclei) may not exceed 120. The periodic table begins with two elements in the s-block and because of its three dimensional symmetry it must end with two element in the same block." dated June 25, 2004.
Few weeks later, on July 19, 2004, and after drawing the author's attention to this web site, Dr. F. W. Giacobbe responded to the preceding comment as follows:
"..Thank you for sending me this web site location. I read the information that was there with interest. Actually, my calculation only predicts a Maximum Z value of about 125. Lower values are probably even more likely, as I mentioned in my paper, because instabilities (i.e., the tendency toward inverse Beta decay) are likely to increase dramatically as Z values approach 125. Taking
into account other effects is certainly likely to drop Maximum Z values even further below 125 as the web site article indicates. In any case, I think time will "tell" but if anyone ever announces Z values for stable nuclei above 125, I would want to see at least a few confirming experimental studies but I don't think that will happen. Thank you again for your note. With Best Regards, FWG .."
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