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Title: Atomic radii for atoms with the 6s shell outermost: The effective atomic radius and the van der Waals radius from {sub 55}Cs to {sub 80}Hg

Abstract

We consider, for atoms from {sub 55}Cs to {sub 80}Hg, the effective atomic radius (r{sub ear}), which is defined as the distance from the nucleus at which the magnitude of the electric field is equal to that in He at one half of the equilibrium bond length of He{sub 2}. The values of r{sub ear} are about 50% larger than the mean radius of the outermost occupied orbital of 6s, . The value of r{sub ear} decreases from {sub 55}Cs to {sub 56}Ba and undergoes increases and decreases with rising nuclear charge from {sub 57}La to {sub 70}Y b. In fact r{sub ear} is understood as comprising two interlaced sequences; one consists of {sub 57}La, {sub 58}Ce, and {sub 64}Gd, which have electronic configuration (4f{sup n−1})(5d{sup 1})(6s{sup 2}), and the remaining atoms have configuration (4f{sup n})(6s{sup 2}). The sphere defined by r{sub ear} contains 85%–90% of the 6s electrons. From {sub 71}Lu to {sub 80}Hg the radius r{sub ear} also involves two sequences, corresponding to the two configurations 5d{sup n+1}6s{sup 1} and 5d{sup n}6s{sup 2}. The radius r{sub ear} according to the present methodology is considerably larger than r{sub vdW} obtained by other investigators, some of who have found valuesmore » of r{sub vdW} close to .« less

Authors:
 [1];  [2];  [3];  [4];  [5]
  1. Graduate School of Natural Sciences, Nagoya City University, Nagoya, Aichi 467-8501 (Japan)
  2. (Japan)
  3. School of Information Science and Technology, Chukyo University, Toyota, Aichi 470-0393 (Japan)
  4. Division of Chemistry, Graduate School of Science, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan)
  5. School of International Liberal Studies, Chukyo University, Nagoya, Aichi 466-8666 (Japan)
Publication Date:
OSTI Identifier:
22493907
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 5; Journal Issue: 6; Other Information: (c) 2015 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; ATOMIC NUMBER; ATOMIC RADII; ATOMS; BOND LENGTHS; CERIUM; CESIUM; ELECTRIC FIELDS; ELECTRONIC STRUCTURE; ELECTRONS; EQUILIBRIUM; GADOLINIUM; HELIUM; LANTHANUM; MERCURY; VAN DER WAALS FORCES; YTTRIUM

Citation Formats

Tatewaki, Hiroshi, E-mail: htatewak@nsc.nagoya-cu.ac.jp, Institute of Advanced Studies in Artificial Intelligence, Chukyo University, Toyota, Aichi 470-0393, Hatano, Yasuyo, Noro, Takeshi, and Yamamoto, Shigeyoshi. Atomic radii for atoms with the 6s shell outermost: The effective atomic radius and the van der Waals radius from {sub 55}Cs to {sub 80}Hg. United States: N. p., 2015. Web. doi:10.1063/1.4922953.
Tatewaki, Hiroshi, E-mail: htatewak@nsc.nagoya-cu.ac.jp, Institute of Advanced Studies in Artificial Intelligence, Chukyo University, Toyota, Aichi 470-0393, Hatano, Yasuyo, Noro, Takeshi, & Yamamoto, Shigeyoshi. Atomic radii for atoms with the 6s shell outermost: The effective atomic radius and the van der Waals radius from {sub 55}Cs to {sub 80}Hg. United States. doi:10.1063/1.4922953.
Tatewaki, Hiroshi, E-mail: htatewak@nsc.nagoya-cu.ac.jp, Institute of Advanced Studies in Artificial Intelligence, Chukyo University, Toyota, Aichi 470-0393, Hatano, Yasuyo, Noro, Takeshi, and Yamamoto, Shigeyoshi. Mon . "Atomic radii for atoms with the 6s shell outermost: The effective atomic radius and the van der Waals radius from {sub 55}Cs to {sub 80}Hg". United States. doi:10.1063/1.4922953.
@article{osti_22493907,
title = {Atomic radii for atoms with the 6s shell outermost: The effective atomic radius and the van der Waals radius from {sub 55}Cs to {sub 80}Hg},
author = {Tatewaki, Hiroshi, E-mail: htatewak@nsc.nagoya-cu.ac.jp and Institute of Advanced Studies in Artificial Intelligence, Chukyo University, Toyota, Aichi 470-0393 and Hatano, Yasuyo and Noro, Takeshi and Yamamoto, Shigeyoshi},
abstractNote = {We consider, for atoms from {sub 55}Cs to {sub 80}Hg, the effective atomic radius (r{sub ear}), which is defined as the distance from the nucleus at which the magnitude of the electric field is equal to that in He at one half of the equilibrium bond length of He{sub 2}. The values of r{sub ear} are about 50% larger than the mean radius of the outermost occupied orbital of 6s, . The value of r{sub ear} decreases from {sub 55}Cs to {sub 56}Ba and undergoes increases and decreases with rising nuclear charge from {sub 57}La to {sub 70}Y b. In fact r{sub ear} is understood as comprising two interlaced sequences; one consists of {sub 57}La, {sub 58}Ce, and {sub 64}Gd, which have electronic configuration (4f{sup n−1})(5d{sup 1})(6s{sup 2}), and the remaining atoms have configuration (4f{sup n})(6s{sup 2}). The sphere defined by r{sub ear} contains 85%–90% of the 6s electrons. From {sub 71}Lu to {sub 80}Hg the radius r{sub ear} also involves two sequences, corresponding to the two configurations 5d{sup n+1}6s{sup 1} and 5d{sup n}6s{sup 2}. The radius r{sub ear} according to the present methodology is considerably larger than r{sub vdW} obtained by other investigators, some of who have found values of r{sub vdW} close to .},
doi = {10.1063/1.4922953},
journal = {AIP Advances},
number = 6,
volume = 5,
place = {United States},
year = {Mon Jun 15 00:00:00 EDT 2015},
month = {Mon Jun 15 00:00:00 EDT 2015}
}
  • The van der Waals C{sub 6} coefficients of fullerenes are shown to exhibit an anomalous dependence on the number of carbon atoms N such that C{sub 6} ∝ N{sup 2.2} as predicted using state-of-the-art quantum mechanical calculations based on fullerenes with small sizes, and N{sup 2.75} as predicted using a classical-metallic spherical-shell approximation of the fullerenes. We use an atomistic electrodynamics model where each carbon atom is described by a polarizable object to extend the quantum mechanical calculations to larger fullerenes. The parameters of this model are optimized to describe accurately the static and complex polarizabilities of the fullerenes bymore » fitting against accurate ab initio calculations. This model shows that C{sub 6} ∝ N{sup 2.8}, which is supportive of the classical-metallic spherical-shell approximation. Additionally, we show that the anomalous dependence of the polarizability on N is attributed to the electric charge term, while the dipole–dipole term scales almost linearly with the number of carbon atoms.« less
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