The promethium (Pm61), the only rare earth element whose chemistry had remained an enigma, begins to reveal its secrets; this element, which has long been relegated to the margins of the periodic table, may not play as crucial a role in society as its more famous neighbors, but recent discoveries they could open up new avenues to access rare earth resources, which are increasingly vital in the modern era.
The category of elements known as “rare earths” has aroused growing interest and, at the same time, a certain confusion, this is because many of these elements are becoming fundamental in various technological sectors, take for example neodymium: this item is essential for producing the most powerful permanent magnetsthus becoming a pillar of the clean energy revolution.
The label “rare earth” has fueled fears that these resources may be insufficient to meet global demand, but the reality is very different: neodymium is almost as abundant in the earth’s crust as copper and much more than lead.
Promethium: an elusive element
Promethium is notable for its extreme rarity, it is one of the most difficult elements to find on our planetexceeding in scarcity even some transuranic elements, which were once thought not to exist in nature. Its discovery occurred only in 1945was late compared to other elements, and its limited presence has made research into its chemistry a little-explored field.
L’Oak Ridge National Laboratory (ORNL), theater of the discovery of promethium, recently decided to deepen its knowledge of this mysterious element, with Dr Alex Ivanoc who explained:
“The goal was to explore this rare element to gain new knowledge”
then adding:
“Realizing that it was discovered right here in our lab, we felt compelled to pursue this research to honor the legacy of ORNL.”
The research team managed to characterize promethium in solution, a feat never achieved before, specifically promethium-147, an isotope produced as a by-product in the manufacture of plutonium. In a symbolic gesture that recalls the mythological figure from which the element takes its name, the researchers linked promethium to organic molecules known as diglycolamide ligands, and through X-ray spectroscopythey measured the length of the bonds between promethium and adjacent atoms, comparing it with that of other lanthanides.
Lanthanide contraction and its implications
The phenomenon known as “lanthanide contraction” has also been confirmed for promethium. This process involves a more pronounced compaction of the electrons around the nucleus compared to other elements, influencing properties such as the physical state at room temperature.
Mercuryfor example, is the only liquid element at room temperature and this is due to this phenomenonspecifically, the reduction in atomic size increases the attraction between the electrons and the nucleus, stabilizing the liquid state of mercury in conditions that would normally see other elements in solid form.
The ORNL team observed that the contraction of chemical bonds intensifies along the series of lanthanide atoms, but slows significantly after promethium. Lanthanide contraction is a fascinating phenomenon which occurs in all the elements of this series, but takes on a particular meaning when talking about promethium as this process, which involves a compaction of the electrons around the nucleus, not only makes the atoms smaller, but also affects their properties chemical and physical in ways that can be surprising.
Promethium follows this trend, although its contraction is less intense than the other lanthanides. This subtle but significant difference contributes to its unique position in the periodic table and could have interesting implications for its chemical properties and behavior.
Another fundamental aspect of the contraction of lanthanides is the role it plays in the separation of rare earth elements, precisely with the growing demand for these precious resources, it becomes increasingly important to find efficient ways to manage their sources. The similar chemistry between the 14 lanthanides makes it difficult to separate them when they are extracted from the same ore, but a thorough understanding of the contraction of each element could provide the key to separating them more effectively.
Promethium, with its extreme rarity and absence of stable isotopes, stands out as a special case among the lanthanideswith its chemical bond contraction being less pronounced, which could affect its chemical properties in ways yet to be discovered.
In conclusion, promethium may not be the most famous of its neighbors in the periodic table, but revelations about its chemistry and lanthanide contraction could open up new opportunities to better manage rare earth resourcesand these discoveries pThey could be the key to meeting growing demand in crucial technological and industrial sectors.
If you are attracted by science or technology, continue to follow us, so you don’t miss the latest news from all over the world!
#Promethium #properties #revealed #years #discovery
