A chemist would know the significance of the periodic table of elements. While probably every person becomes familiar with it from the earliest stages of their education. Moreover, certain people have great affection for it for example; did you know that Bill Gates has a Periodic Table of his own with actual samples of each element.
In the beginning, Russian chemistry professor Dmitri Mendeleev and German chemist Julius Lothar Meyer independently published their periodic tables in 1869 and 1870, respectively. Mendeleev’s table, dated March 1, 1869, was his first published version. Both of them designed their periodic tables by listing the elements in rows or columns in order of atomic weight and starting a new row or column when the characteristics of the elements began to repeat. The elements classifies into three categories — metals, metalloids, and non-metals, with respect to their shared physical and chemical properties.
Today in the modern periodic table the elements are ordered by atomic number (the number of positively charged particles called protons in the atomic nucleus), rather than by atomic mass, but still also by chemical similarities.
New arrangement scheme
The newest attempt to order elements in this manner was freshly published in “The Journal of Physical Chemistry” by scientists Zahed Allahyari and Artem Oganov. Their perspective, building on the earlier work of others, is to assign to each element what’s called a Mendeleev Number (MN). There are several ways to derive such numbers, but the latest study uses a combination of two fundamental quantities that can be measured directly: an element’s atomic radius and a property called electronegativity which describes how strongly an atom attracts electrons to itself.
What is Mendeleev Number (MN)?
The Mendeleev number is an ordering number attributed to each chemical element in the periodic system with the aim to order them so that chemical elements with a similar behavior follow each other.
If one directs the elements by their Mendeleev number (MN), then the nearest neighbors will have, unsurprisingly, similar Mendeleev numbers (MN). But this can be more beneficial if practiced one step further and build a two-dimensional grid based on the Mendeleev number (MN) of the fundamental elements in so-called “binary compounds.” These are the compounds that are composed of two elements, such as sodium chloride (NaCl).
What is the benefit of this approach?
It will help to predict the characteristics of binary compounds that haven’t been invented still. Maybe it is useful in the search for new materials that will be needed for future designs. In time, no doubt, this will be extended to compounds with more than two elemental components. Moreover, the world is getting out of the rare elements and there is no doubt of extinction in the future.
For example, take your smartphone that is made up of some 30 elements and all of them are becoming a rarity. If we are to develop replacement materials that avoid the use of certain elements, the insights gained from ordering elements by their Mendeleev number (MN) may prove valuable in that search. After 150 years, the periodic tables are not just a vital educational tool, they also remain useful for researchers in their hunt for essential new materials.