Electron River...

A river made of graphene with the electrons flowing like water.
Courtesy: Ryan Allen and Peter Allen, Second Bay Studios

Topics: Electron Configuration, Graphene, Nanotechnology

Electrons can behave like a viscous liquid as they travel through a conducting material, producing a spatial pattern that resembles water flowing through a pipe. So say researchers in Israel and the UK who have succeeded in imaging this hydrodynamic flow pattern for the first time using a novel scanning probe technique. The result will aid developers of future electronic devices, especially those based on 2D materials like graphene in which electron hydrodynamics is important.

We are all familiar with the distinctive patterns formed by water flowing in a river or stream. When the water encounters an obstacle – such as the river bank or a boat – the patterns change. The same should hold true for electron flow in a solid if the interactions between electrons are strong. This rarely occurs under normal conditions, however, since electrons tend to collide with defects and impurities in the material they travel through, rather than with each other.

Making electrons hydrodynamic

Conversely, if a material is made very clean and cooled to low temperatures, it follows that electrons should travel across it unperturbed until they collide with its edges and walls. The resulting ballistic transport allows electrons to flow with a uniform current distribution because they move at the same rate near the walls as at the center of the material.

If the temperature of this material is then increased, the electrons can begin to interact. In principle, they will then scatter off each other more frequently than they collide with the walls. In this highly interacting, hydrodynamic regime, the electrons should flow faster near the center of a channel and slower near its walls – the same way that water behaves when it flows through a pipe.

Electrons flow like water in ultra-pure graphene, Belle Dumé, Physics World

Yotta Years...

The Borexino detector comprises 300 tonnes of an organic liquid that is viewed by 2212 photomultipliers. The Borexino detector has not seen evidence for electron decay (Courtesy: Borexino Collaboration)

Topics: Chemistry, Electron Configuration, Particle Physics, Nuclear Physics, Theoretical Physics

Yotta is the largest decimal unit prefix in the metric system, denoting a factor of 10²⁴ or 1,000,000,000,000,000,000,000,000. It has the unit symbol Y. The prefix name is derived from the Ancient Greek οκτώ (októ), meaning "eight", because it is equal to 1000⁸. Wikipedia

The best measurement yet of the lifetime of the electron suggests that a particle present today will probably still be around in 66,000 yottayears (6.6 × 10²⁸ yr), which is about five-quintillion times the current age of the universe. That is the conclusion of physicists working on the Borexino experiment in Italy, who have been searching for evidence that the electron decays to a photon and a neutrino; a process that would violate the conservation of electrical charge and point towards undiscovered physics beyond the Standard Model.

The electron is the least-massive carrier of negative electrical charge known to physicists. If it were to decay, energy conservation means that the process would involve the production of lower-mass particles such as neutrinos. But all particles with masses lower than the electron have no electrical charge, and therefore the electron's charge must "vanish" during any hypothetical decay process. This violates "charge conservation", which is a principle that is part of the Standard Model of particle physics. As a result, the electron is considered a fundamental particle that will never decay. However, the Standard Model does not adequately explain all aspects of physics, and therefore the discovery of electron decay could help physicists to develop a new and improved model of nature.

Physics World: Electron lifetime is at least 66,000 yottayears, Hamish Johnston

Breaking The Rules...

UNUSUAL BONDS: Chemical bonds between cesium (Cs) and fluorine (F) might form with not just valence electrons, but inner-shell electrons as well under very high pressures, new calculations suggest.
Image: Maosheng Miao

A study suggests atoms can bond not only with electrons in their outer shells, but also via those in their supposedly sacrosanct inner shells

By Clara Moskowitz

Most of us learned in high school chemistry class that chemical bonds can only form when electrons are shared or given away from one atom’s outer shell to another’s. But this may not be strictly true. A chemist has calculated that under very high pressure not just the outer electrons but the inner ones, too, could form bonds.

Inside atoms, electrons are organized into energy levels, called shells, which can be thought of as buckets of increasing size that can each hold only a fixed number of electrons. Atoms prefer to have filled buckets, so if their outer shell is missing just one or two electrons, they are eager borrow form another atom that might have one or two to spare. But sometimes, a new study suggests, atoms can be incited to share not just their outer valence electrons, but those from their full inner shells. “It breaks our doctrine that the inner-shell electrons never react, never enter the chemistry domain,” says Mao-sheng Miao, a chemist at the University of California, Santa Barbara, and the Beijing Computational Science Research Center in China. Miao predicted such bonds using so-called first-principles calculations, which rely purely on the known laws of physics, and reported his findings in a paper published September 23 in Nature Chemistry. Such bonding has yet to be demonstrated in a lab. Nevertheless, “I’m very confident that this is real,” he says. (Scientific American is part of Nature Publishing Group.)

Scientific American: A Basic Rule of Chemistry Can Be Broken

Birthday Wishes...

Electron Configuration: Think Quest

Electrons rule our world, but not so long ago they were only an idea. This month marks the 120th anniversary of a profound and influential creation, the electron theory of Dutch physicist Hendrik Antoon Lorentz. His electron was not merely a hypothesized elementary particle; it was the linchpin of an ambitihous theory of nature. Today physicists are accustomed to the notion that a complete description of nature can rise out of simple, beautiful equations, yet prior to Lorentz that was a mystic vision.

Scientific American: Happy Birthday, Electron!
Nobel Prize: Hendrik Antoon Lorentz

Millikan...and me

The Millikan oil drop experiment, published in final form in 1913, demonstrated that charge comes in discrete chunks and was a bridge between classical electromagnetism and modern quantum physics.

I didn't know that the value and how he'd reached that value was controversial at the time. I post this not just because of the historic significance, but that I taught at Manor High School with Gary Millikan, I believe he described Dr. Millikan as a "great-grand uncle," and himself as a black sheep: he teaches world geography, I taught physics. It was when I taught this module I quizzed Gary, and discovered his remarkable ancestry.

APS: Landmarks–Millikan Measures the Electron’s Charge

The Physics of Lightning...

"Now, if you can separate these ions from one another, you create a separation of charge, which creates a Voltage. When the Voltage (also known as the electric potential difference) between two regions becomes too great -- even if air is the only thing between them -- it will spontaneously become conductive, and the rapid exchange of charge is what you see as a lightning strike!" Science Blogs

I admit: as a child, lightning frightened me. I still give it deep respect (and, I'm too big to dive under the bed anymore). So, if it's safe, I tend to do what my father did: look at it.

This simple exchange of sodium and chloride ions (i.e. salt: see Science Blog link), is all that the phenomena is:

100,000,000,000,000,000,000 = 10²⁰ electrons are exchanged in a single bolt:

I suppose: a dive for the bed would have warranted if I'd seen this display (if he physically could have, maybe Pop would have joined me):



 Eyjafjallajökull eruption


Science Blogs "Starts With a Bang": The Amazing Phenomenon of Volcanic Lightning!

1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p1 still = [Ar] 4s2 3d10 4p1...

...that is, the electron configuration for Galium (31),  This is only about atomic weights,  I was just having fun!  :-)

Now the International Union of Pure and Applied Chemists has decided to display the atomic weights of 10 elements as a range, rather than a single, average value.


Those elements affected are: hydrogen, lithium, boron, carbon, nitrogen, oxygen, silicon, sulfur, chlorine and thallium. Some elements, such as fluorine and gold, only exist in one form, so their weights are fixed.

New Scientist: "Immutable" periodic table taken in for alterations

Electron configuration sites:

1. Electron configuration for all elements on the periodic table
2. Dr. Michael Blaber: Professor of Biomedical Sciences at Florida State University: Electronic Structure of Atoms