Ligand field stabilization energies and stereochemistry of early second and third row transition elements

1968 ◽  
Vol 21 (1) ◽  
pp. 9 ◽  
Author(s):  
R Colton ◽  
JH Canterford
Keyword(s):  
Periodic Table ◽  
Ligand Field ◽  
Transition Elements ◽  
Transition Series ◽  
Stabilization Energies

The elements of the second and third row transition series towards the left of the Periodic Table show clearly defined trends in their observed stereochemistries. These trends are summarized and an explanation for the experimental facts is suggested.

Thermodynamic of metal complexation of the macrocyclic antibiotic rifampicin

2001 ◽  
Vol 79 (1) ◽  
pp. 42-49
Author(s):  
I Shehatta ◽  
I Kenawy ◽  
A H Askalany ◽  
Ayman A Hassan
Keyword(s):  
Binding Sites ◽  
Equilibrium Constants ◽  
Ionic Species ◽  
Ligand Field ◽  
Water Medium ◽  
Acid Base ◽  
Distribution Diagram ◽  
Macrocyclic Antibiotic ◽  
Transition Series ◽  
Different Temperatures

The acid-base and complexation equilibria of rifampicin with H+, Mn2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+, and Pb2+ were studied by means of potentiometry. The stoichiometric equilibrium constants were determined in 50% (v/v) methanol-water medium at different temperatures and constant ionic strength (0.05 M KCl). It was established that rifampicin has two proton-binding sites. The distribution diagram of the corresponding ionic species as a function of pH is given and indicated that rifampicin exists predominantly in the zwitterionic form at pH [Formula: see text] 5. The thermodynamic parameters of protonation and complexation were derived and discussed. The formation of the complexes is spontaneous, more favourable at lower temperatures, entropically unfavourable, and an enthalpy-driven process. The order of the changes in Gibbs energy and enthalpy accompanying the complexation was found to be Mn2+ < Co2+ < Ni2+ < Cu2+ > Pb2+ > Zn2+ > Cd2+ > Hg2+ in accordance with the well-known sequence of Irving and Williams. The transition series contraction energy (Er(Mn-Zn)), and the ligand field stabilization energy (δH) were calculated from the enthalpy changes.Key words: rifampicin, thermodynamics, potentiometry, and complexation.

Metal complexes in soils.

1955 ◽  
Vol 6 (5) ◽  
pp. 685 ◽  
Author(s):  
RS Beckwith
Keyword(s):  
Metal Ions ◽  
Metal Complexes ◽  
Periodic Table ◽  
Organic Soils ◽  
Titration Curves ◽  
Transition Series ◽  
Presence And Absence

The release of manganese from organic soils by copper has been studied. The results obtained together with the titration curves of acid-washed organic soils, determined in the presence and absence of various added metal ions, support the suggestion of Bremner et al. (1946) that the metals of the first transition series of the periodic table are held in organic soils as complexes. The consequences of the results are discussed particularly in regard to the release of metal ions from soils and their uptake by plants.

scholarly journals The role of copper in the Electronics Industry as an interconnecting agent

2011 ◽  
pp. 53-56
Author(s):  
Gangotri Dey
Keyword(s):  
Integrated Circuit ◽  
Periodic Table ◽  
Electronics Industry ◽  
The Other ◽  
Transition Elements ◽  
Number Of Components ◽  
Nickel Cobalt ◽  
Iron Nickel ◽  
Over Time

Mendeleev to Periodic table: “Dear PT, according to you, which is the most boring element of them all?” PT: “My Lord, Maybe copper?” Mendeleev: “Why do you say this?” PT: “It gets very boring for me. Unlike the other transition elements, for example iron, nickel, cobalt, which show magnetism, copper has no choice but to settle with one spin. Such monotony in spin makes it quite boring, I think.” Mendeleev:- “Do you understand the beauty of copper? Do you know that it could change the modern electronics industry?” PT: “No, never thought of that.” Mendeleev: “Then listen to me carefully. During the 1960's, Gordon Moore predicted that, in the electronics industry, the number of components that could be assembled within one integrated circuit (IC) would increase exponentially over time, and thus also the size of a fully operational IC would be reduced. Indeed, this turned out to be true in ...

scholarly journals On the Regularity of the Electron Configuration of Atoms in the Periodic Table

2021 ◽  
Author(s):  
Toshihiro Konishi ◽  
Ryosuke Miura
Keyword(s):  
Energy Level ◽  
Chemical Reactions ◽  
Basic Principle ◽  
Periodic Table ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Electron Configuration ◽  
Transition Elements ◽  
Complex Chemical ◽  
Complex Chemical Reactions

Abstract The current periodic table does not necessarily have a clear position for transition elements. Therefore, the purpose of this paper is to use the basic principle discovered by Mendeleev as it is and to create a periodic ta ble with consistency for transition elements. By setting some hypotheses, it was found that transition elements also have regular periodicity, so we succeeded in clarifying the energy level of electrons in each orbit. In addition, by utilizing its periodic ity, the electron configuration for each orbit was predicted for unknown elements. In this paper, we did not take the conventional idea of electron orbitals, that is, the idea of forming a hybrid orbital, but assumed a new orbital.Since the state in which electrons fit in orbits and stabilize is defined as an octet, this idea was used as the basic principle in this paper, but the hypothesis that "there are only three orbits in each shell" was established and verified.The calculatio n of the energy level of the electrons on the orbit became extremely easy, and the order of each orbit could be clarified. It was also found that the three dimensional structure of the molecule may be visualizedby paying attention to the valence electrons of the outermost shell of the element and the octet of the stability condition. Therefore, in this paper, by slightly expanding the structural formula of Kekulé, it became possible to easily determine whether or not the molecule synthesized by the became possible to easily determine whether or not the molecule synthesized by the bond bebond between elements is stable.tween elements is stable. In addition, it has become possible to predict the three In addition, it has become possible to predict the three--dimensional structure of the dimensional structure of the molecule as well.molecule as well. Furthermore, not only will it be easier for students studying chemistry to understand Furthermore, not only will it be easier for students studying chemistry to understand complex chemical reactions, but it will complex chemical reactions, but it will also be useful for researchers in the development also be useful for researchers in the development and research of new drugs.and research of new drugs.

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