A NEW FORMULA FOR THE EVALUATION OF THE IONIZATION ENERGY BASED ON THE ORBITAL EXPONENTS OF THE ATOMS OF 118 ELEMENTS OF THE PERIODIC TABLE

We propose a simple approach for the calculation of the ionization potentials of atoms in terms of their orbital exponents. The prescription is simple and utilizes only the simple Bohr equation with some modifications. We have pointed out that the atomic first ionization energy not only depends on the principal quantum number (n) but also on the azimuthal quantum number (l) of the orbital (n, l) on which the electron of interest is present. The formalism is tested through the calculation of the atomic ionization potentials of 118 elements of the periodic table. The orbital exponent values for 118 elements of the periodic table are computed following the suggestions of Reed. The calculated numerical results for a number of atoms are shown to agree quite well with their experimental counterparts. To perform the validity tests of the present scale of ionization potential, various physico-chemical properties of the atoms are also correlated on the basis of the computed ionization potential data. It is found that the stability of the half filled configuration depends on the orbital (n, l) on which the electron is present. The expressed periodic behavior and correlation of the most important physico-chemical properties of elements suggest that the present method of evaluation of the ionization potential of the atoms is quite a successful venture.

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Comments on the paper by A. D. Walsh

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1951.0096 ◽

1951 ◽

Vol 207 (1088) ◽

pp. 31-32 ◽

Cited By ~ 2

Keyword(s):

Ionization Potential ◽

Ground State ◽

Valence State ◽

Periodic Table ◽

Direct Relationship ◽

Ionization Potentials ◽

Electron Affinities ◽

Theoretical Justification ◽

Left Hand ◽

The Right

Theoretical justification for a relationship between ionization potential ( I ) and electronegativity ( x ) rests in the equation derived by Mulliken (1934, 1949), viz.: X = I + E / 2 where E is the electron affinity. Elements situate on the left-hand side of the Periodic Table have small E values, so that in these cases a direct relationship between x and I might be anticipated. On the right-hand side of the Periodic Table, the electron affinities may be appreciable, and for example in the halogens, are of the order 3 to 4 eV. The neglect of the term in E in these instances represents a serious departure from Mulliken’s equation. It is furthermore important to stress that the values of I which apply in the Mulliken equation are ‘valence-state’ ionization potentials, and are not in general to be identified with the first ionization potentials of the elements, which Walsh has employed. The relationships observed by Walsh might, in consequence, be misleading in cases where the ionization potential of the ground-state of an atom is far removed (in energy) from the ionization potential of the atom in its appropriate valence-state (e.g. Zn, Cd, Hg).

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Molecular ionization potential and dissociation energies related to atomic ionization potentials for singly bonded diatomics

The Journal of Chemical Physics ◽

10.1063/1.442018 ◽

1981 ◽

Vol 75 (12) ◽

pp. 5789-5790 ◽

Cited By ~ 12

Author(s):

J. F. Mucci ◽

N. H. March

Keyword(s):

Ionization Potential ◽

Ionization Potentials ◽

Dissociation Energies ◽

Atomic Ionization ◽

Molecular Ionization

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The relation between successive atomic ionization potentials

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1978.0054 ◽

1978 ◽

Vol 359 (1699) ◽

pp. 525-543 ◽

Cited By ~ 17

Keyword(s):

Angular Momentum ◽

Simple Model ◽

Linear Relation ◽

Periodic Table ◽

Nuclear Charge ◽

Ionization Potentials ◽

Total Charge ◽

Intrinsic Properties ◽

Atomic Ionization ◽

Ionization Processes

A quantitatively accurate, yet conceptually simple model of successive atomic ionization processes is presented and verified computationally for the valence shells of atoms drawn from the entire periodic table. The linear relation between successive ionization potentials for valence s or p electrons is explained. The failure of d or f electron ionization to show the same behaviour is interpreted as a consequence of their larger angular momentum, leading to relatively weaker binding compared with s or p orbitals of the same mean radii. It is not due to changes in the intrinsic properties of the orbitals themselves. The concept that the properties of d or f orbitals are especially sensitive to the total charge of an ion is found to be misleading provided the nuclear charge is kept constant.

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Chemistry of silver(II): a cornucopia of peculiarities

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2014.0179 ◽

2015 ◽

Vol 373 (2037) ◽

pp. 20140179 ◽

Cited By ~ 26

Author(s):

Wojciech Grochala ◽

Zoran Mazej

Keyword(s):

Thermal Decomposition ◽

High Pressure ◽

Spin Polarization ◽

Periodic Table ◽

Chemical Properties ◽

Cationic Form ◽

Physico Chemical ◽

Jahn Teller ◽

Jahn Teller Effect ◽

Strong Spin

Silver is the heavier congener of copper in the Periodic Table, but the chemistry of these two elements is very different. While Cu(II) is the most common cationic form of copper, Ag(II) is rare and its compounds exhibit a broad range of peculiar physico-chemical properties. These include, but are not limited to: (i) uncommon oxidizing properties, (ii) unprecedented large mixing of metal and ligand valence orbitals, (iii) strong spin-polarization of neighbouring ligands, (iv) record large magnetic superexchange constants, (v) ease of thermal decomposition of its salts with O-, N- or C-ligands, as well as (vi) robust Jahn–Teller effect which is preserved even at high pressure. These intriguing features of the compounds of Ag(II) will be discussed here together with (vii) a possibility of electromerism (electronic tautomerism) for a certain class of Ag(II) salts.

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Decoration of specific sites on freeze-fractured membranes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081565 ◽

1978 ◽

Vol 36 (2) ◽

pp. 140-141

Author(s):

H. Gross ◽

H. Moor

Keyword(s):

Pure Water ◽

Freeze Fracture ◽

Chemical Properties ◽

Surface Forces ◽

Sulfate Pentahydrate ◽

Copper Sulfate Pentahydrate ◽

Physico Chemical ◽

Water Of Hydration ◽

Small Container ◽

Binding Forces

Fracturing under ultrahigh vacuum (UHV, p ≤ 10-9 Torr) produces membrane fracture faces devoid of contamination. Such clean surfaces are a prerequisite foe studies of interactions between condensing molecules is possible and surface forces are unequally distributed, the condensate will accumulate at places with high binding forces; crystallites will arise which may be useful a probes for surface sites with specific physico-chemical properties. Specific “decoration” with crystallites can be achieved nby exposing membrane fracture faces to water vopour. A device was developed which enables the production of pure water vapour and the controlled variation of its partial pressure in an UHV freeze-fracture apparatus (Fig.1a). Under vaccum (≤ 10-3 Torr), small container filled with copper-sulfate-pentahydrate is heated with a heating coil, with the temperature controlled by means of a thermocouple. The water of hydration thereby released enters a storage vessel.

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PHYSICO CHEMICAL PROPERTIES OF NICKEL OXIDE AT HIGH TEMPERATURE

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1976798 ◽

1976 ◽

Vol 37 (C7) ◽

pp. C7-438-C7-442 ◽

Cited By ~ 2

Author(s):

R. FARHI ◽

G. PETOT-ERVAS

Keyword(s):

High Temperature ◽

Nickel Oxide ◽

Chemical Properties ◽

Physico Chemical

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g-HARTREE AB-INITIO CALCULATION OF ATOMIC IONIZATION ENERGY

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1987983 ◽

1987 ◽

Vol 48 (C9) ◽

pp. C9-509-C9-512

Author(s):

M. OHNO

Keyword(s):

Ab Initio ◽

Ionization Energy ◽

Ab Initio Calculation ◽

Atomic Ionization

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Physico-Chemical Properties of Recombinant Desulphatohirudin

Thrombosis and Haemostasis ◽

10.1055/s-0038-1645073 ◽

1990 ◽

Vol 63 (03) ◽

pp. 499-504 ◽

Cited By ~ 4

Author(s):

A Electricwala ◽

L Irons ◽

R Wait ◽

R J G Carr ◽

R J Ling ◽

...

Keyword(s):

Molecular Weight ◽

Gel Filtration ◽

Chemical Properties ◽

Alpha Helix ◽

Apparent Molecular Weight ◽

Correlation Spectroscopy ◽

Nmr Studies ◽

Recombinant Hirudin ◽

Physico Chemical ◽

Recombinant Molecule

SummaryPhysico-chemical properties of recombinant desulphatohirudin expressed in yeast (CIBA GEIGY code No. CGP 39393) were reinvestigated. As previously reported for natural hirudin, the recombinant molecule exhibited abnormal behaviour by gel filtration with an apparent molecular weight greater than that based on the primary structure. However, molecular weight estimation by SDS gel electrophoresis, FAB-mass spectrometry and Photon Correlation Spectroscopy were in agreement with the theoretical molecular weight, with little suggestion of dimer or aggregate formation. Circular dichroism studies of the recombinant molecule show similar spectra at different pH values but are markedly different from that reported by Konno et al. (13) for a natural hirudin-variant. Our CD studies indicate the presence of about 60% beta sheet and the absence of alpha helix in the secondary structure of recombinant hirudin, in agreement with the conformation determined by NMR studies (17)

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