اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدThe periodic table of the elements with $4n^{2}$ $n=2,3,dots$ periods
108
0
0.0
(
0
)
تأليف
Gregory Beylkin
اسأل ChatGPT حول البحث
ﻻ يوجد ملخص باللغة العربية
A modification of the standard periodic table of the elements reveals $4n^{2}$ periods, where $n=2,3,dots$. The new arrangement places hydrogen with halogens and keeps the rare-earth elements in the table proper (without separating them as they are in the standard table). Effectively, periods in the modified table are defined by the halogens rather than by the noble gases. The graph of ionization energy of the elements is presented for comparison of periods in the standard and the modified tables.
قيم البحث
اقرأ أيضاً
We show that the dependence of the total energy of the atoms on their atomic number follows a q-exponential (function proposed by C. Tsallis), for almost all elements of the periodic table. The result is qualitatively explained in terms of the way th
e atomic configurations are arranged to minimize energy.
Predicting the transition temperature, Tc, of a superconductor from Periodic Table normal state properties is regarded as one of the grand challenges of superconductivity. By studying the correlations of Periodic Table properties with known supercond
uctors, it is possible to estimate their transition temperatures. Starting from the isotope effect and correlations of superconductivity with electronegativity (Chi), valence electron count per atom (Ne), atomic number(Z) and formula weight (Fw), we derive an empirical formula for estimating Tc that includes an unknown parameter,(Ko). With average values of Chi, Ne and Z, we develop a material specific characterization dataset (MSCD) model of a superconductor that is quantitatively useful for characterizing and comparing superconductors. We show that for most superconductors, Ko correlates with Fw/Z, Ne, Z, number of atoms (An) in the formula, number of elements (En) and with Tc. We study some superconductor families and use the discovered correlations to predict similar and novel superconductors and also estimate their Tcs. Thus the material specific equations derived in this paper, the material specific characterization dataset (MSCD) system developed here and the discovered correlation between Tc and Fw/Z, En and An, provide the building blocks for the analysis, design and search of potential novel high temperature superconductors with specific estimated Tcs.
A large variety of periodic tables of the chemical elements have been proposed. It was Mendeleev who proposed a periodic table based on the extensive periodic law and predicted a number of unknown elements at that time. The periodic table currently u
sed worldwide is of a long form pioneered by Werner in 1905. As the first topic, we describe the work of Pfeiffer (1920), who refined Werners work and rearranged the rare-earth elements in a separate table below the main table for convenience. Todays widely used periodic table essentially inherits Pfeiffers arrangements. Although long-form tables more precisely represent electron orbitals around a nucleus, they lose some of the features of Mendeleevs short-form table to express similarities of chemical properties of elements when forming compounds. As the second topic, we compare various three-dimensional helical periodic tables that resolve some of the shortcomings of the long-form periodic tables in this respect. In particular, we explain how the 3D periodic table Elementouch (Maeno 2001), which combines the s- and p-blocks into one tube, can recover features of Mendeleevs periodic law. Finally we introduce a topic on the recently proposed nuclear periodic table based on the proton magic numbers (Hagino and Maeno 2020). Here, the nuclear shell structure leads to a new arrangement of the elements with the proton magic-number nuclei treated like noble-gas atoms. We show that the resulting alignments of the elements in both the atomic and nuclear periodic tables are common over about two thirds of the tables because of a fortuitous coincidence in their magic numbers.
The fundamental organizing principle resulting in the periodic table is the nuclear charge. Arranging the chemical elements in an increasing atomic number order, a symmetry pattern known as the Periodic Table is detectable. The correlation between nu
clear charge and the Periodic System of the Chemical Elements (PSCE) indicates that the symmetry emerges from the nucleus. Nuclear symmetry can only exist if the relative positions of the nucleons in the nucleus are invariant. Pauli exclusion principle can also be interpreted as the nucleons should occupy a lattice position. Based on symmetry and other indicatives face centered cubic arrangement have been proposed for the nuclear lattice. A lattice model, representing the protons and the neutrons by equal spheres and arranging them alternately in a face centered cubic structure forming a double tetrahedron, is able to reproduce all of the properties of the nucleus including the quantum numbers and the periodicity of the elements. Based on the geometry of the nuclear structure it is shown that when a new layer of the nuclear structure starts then the distance between the first proton in the new layer and the charge center of the nucleus is smaller than the distance of the proton, which completed the preceding layer. Thus a new valence electron shell should start to develop when the nuclear structure is expanded. The expansion of the double tetrahedron FCC nuclear lattice model offers a feasible physical explanation how the nucleus affects the electronic configuration of the chemical elements depicted by the periodic table.
We explore the reach of low-background experiments made of small quantities of heavy nuclear isotopes in probing the parameter space of inelastic dark matter that is kinematically inaccessible to classic direct detection experiments. Through inelasti
c scattering with target nuclei, dark matter can yield a signal either via nuclear recoil or nuclear excitation. We present new results based on this approach, using data from low-energy gamma quanta searches in low-background experiments with Hf and Os metal samples, and measurements with CaWO$_4$ and PbWO$_4$ crystals as scintillating bolometers. We place novel bounds on WIMPy inelastic dark matter up to mass splittings of about 640 keV, and provide forecasts for the reach of future experiments.
سجل دخول لتتمكن من نشر تعليقات
التعليقات
جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
