Sciencemadness Discussion Board

Anyone experiment with paramagnetic liquids?

Neal - 14-1-2023 at 19:16

Most liquids in room temperatures are diamagnetic, like TiCl4. But VCl4 is 1 of the few paramagnetic liquids out there at room temperature. What kind of experiments can be done with that?

And what other liquids are paramagnetic at room temperature, besides VCl4.


Mateo_swe - 17-1-2023 at 06:44

Not what you asked but a bit related and quite cool.

If one take a little bit of ferrofluid and put it between 2 round plexiglass sheets (or glass) then glue up the edges with superglue.
You get a round piece of plexi that when put in a magnetic field and illuminated will show the magnetic lines in a most beautiful way.
One can put RGB diodes around it and it get super nice looking.
There is a commersial product called a ferrocell but the DIY variant works too.

For example

Neal - 26-6-2023 at 07:30

So while VCl4 seems to be the only paramagnetic liquid out there for inorganic liquids, turns out there are more paramagnetic liquids in the world of organometallic liquids.

Also how do we measure how paramagnetic or diamagnetic a substance is? Are there any liquids that are more diamagnetic than water?

DraconicAcid - 26-6-2023 at 10:44

You can measure the magnetic susceptibility of a compound with a gouy balance. The more unpaired electrons it has, the more paramagnetic.

If it's diamagnetic, it has a magnetic susceptibility of zero. I'm not sure that one material can be more diamagnetic than another.

ETA: Wikipedia tell me I'm wrong. "Diamagnetic materials, like water, or water-based materials, have a relative magnetic permeability that is less than or equal to 1, and therefore a magnetic susceptibility less than or equal to 0, since susceptibility is defined as χv = μv − 1. This means that diamagnetic materials are repelled by magnetic fields. However, since diamagnetism is such a weak property, its effects are not observable in everyday life. For example, the magnetic susceptibility of diamagnets such as water is χv = −9.05×10−6. The most strongly diamagnetic material is bismuth, χv = −1.66×10−4, although pyrolytic carbon may have a susceptibility of χv = −4.00×10−4 in one plane. Nevertheless, these values are orders of magnitude smaller than the magnetism exhibited by paramagnets and ferromagnets. Because χv is derived from the ratio of the internal magnetic field to the applied field, it is a dimensionless value. "

I guess I didn't get the full story as an undergrad.

[Edited on 26-6-2023 by DraconicAcid]

Morgan - 26-6-2023 at 16:18

Although not on topic of a liquid but a tidbit on paramagnetism that suggests something out of the ordinary. Perhaps something to test by using an ordinary US nickel.
"A nickel is a five-cent coin struck by the United States Mint. Composed of cupronickel (75% copper and 25% nickel), the piece has been issued since 1866. "

"For amounts of nickel from one percent up to 30 percent the alloy, while paramagnetic in most respects, does not obey any known law of paramagnetism with regard to temperature. As the temperature is increased the susceptibility first increases and then decreases, the maximum occurring in the neighborhood of the Curie point for nickel." (Nickel has a Curie point of 354° C)
Magnetic Properties of Copper-Nickel Alloys

Σldritch - 27-6-2023 at 01:41

I've tried to come up with paramagnetic gases, myself. There's Cobalt Tetrafluoride of course. Should have very high magnetic moment with the potential of being isoelectronic with the Tetrachloroferrate(III) anion. Kinetic barrier to decomposition of 31 kcal/mol IIRC which could mean it would be stable at room temperature. It is just that the 30 kcal/mol rule of thumb is displaced in the gas phase to 37 kcal/mol IIRC. So close! However as a cryogenic liquid it might be stable-ish and very paramagnetic. Maybe you could even play with it and one of those nickel plated neodymium magnets. Just don't get fluorinated!

Then there is the lathanides and actinides. Perhaps Holmium Hexafluoride would be a stable-ish gas? The 6+ state of Holmium would then have the f-shell move close to the core in a stable half-filled configuration leaving a very hard lewis acidic atom. That, at least is favorable for a stable, covalent, fluoride. In other words a gas/liquid. Essentially paramagnetic tungsten hexafluoride. Perhaps possible, I have not found any studies on its possible existence, however. The actinides are no help here; the later ones being too radioactive.

You already mentioned the organometallic paramagnetic liquids...