Sciencemadness Discussion Board - Interesting rare earth metals (lanthanoids) and thier salts

Interesting rare earth metals (lanthanoids) and thier salts

Antwain - 6-10-2007 at 12:28

Forgive me if there is a thread already about this, I looked and couldn't find one. There are several others concerning obtaining these metals and dealing with some specific ones. I am curious as to which of these metals and their salts are the most interesting from the point of view of the amateur chemist.

For example, I would not consider neodymium interesting because it can make very strong magnets with boron and iron, simply because it is far beyond my abilities to make these magnets myself with the equipment I have on hand. Something That I would consider interesting is europium oxide (Eu2O3), because this substance is (I believe) very strongly fluorescent under UV.

I may decide to buy some rare earth metals soon and since I can't afford to buy them all I would be interested to know if there are some more 'fun' ones that I definitely must get.

Nerro - 6-10-2007 at 13:32

Eu2O3 in itsself is not phosphorescent under a UV lamp, it's the Y2O3 doped variety of Eu2O3 that ís. I've made it once for a practicum. It shines a ghostly red under a UV light. Dissolving both the oxides in nitric acid and then subsequently precipitating it using ammonia was how we mixed the two intimately. Glowing it in an oven at 950°C for a few hours then removed everything but the mixed oxides. (I believe some oxalic acid was added a flux of sorts...)

chloric1 - 6-10-2007 at 15:20

@Antwain-You should check out pottery suppliers. In The USA I know of at least 2 that sell rare earth oxides. They are not reagent grade but they will be good enough for folling around and alot cheaper.

unionised - 7-10-2007 at 01:41

"Eu2O3 in itsself is not phosphorescent under a UV lamp, it's the Y2O3 doped variety of Eu2O3 that ís. "
Are you sure that's the right way round? I think it's Eu doped Y2O3 that glows.
There are certainly Eu compounds that glow red without any Y compounds.

Sauron - 7-10-2007 at 02:03

I think you mean lanthanides not lanthanoids.

Antwain - 7-10-2007 at 02:34

Quote:

Originally posted by Sauron
I think you mean lanthanides not lanthanoids.

Possibly I do, but I copied the spelling verbatim from the periodic table on the wall half a meter to my left.

Sauron - 7-10-2007 at 08:21

Sorry, but I believe that if you check you will find that your periodic table is in error.

Lanthanides, not Lanthanoids

Antinides not Actinoids

[Edited on 7-10-2007 by Sauron]

chemkid - 7-10-2007 at 08:27

Perhaps lanthanoids is an antiquated term for I have seen it used as well. Spell checkers don't seem to like it though.

Chemkid

not_important - 7-10-2007 at 08:31

From 2004

Quote:

IUPAC suggest but do not required lanthanoid and actinoid on the grounds that "-ide" inferrs a negative charge. Some newer books are switching to -oids, inertia rules the rest?

http://www.webelements.com/nexus/node/140

http://www.iupac.org/reports/provisional/abstract04/RB-prs31...

Sauron - 7-10-2007 at 08:39

Yes, I just found that as well. In this instance I think IUPAC is not serving chemistry well, but, there it is.

Their argument is that the -ide suffix should only be used to denote negative ions.

However, I am an old dog and resist new tricks. It is obvious that all of the traditional chemical names that contain such minor inconsistencies cannot be resolved in such a fashion without creating chaos.

In any case Antwain's periodic chart is merely indulging in a current fashion, it is not incorrect, merely nontraditional.

woelen - 7-10-2007 at 09:51

Lanthanon is another name for lanthanide or lanthanoid. Terrible, all these naming conventions.

If you want interesting chemistry with any of the "rare" earths, then you could go for cerium (also one of the cheapest) or neodymium or praseodymium.

Cerium has a nice coordination and redox chemixtry in water. It has some intensely colored compounds and with some luck you can find salts of cerium(IV).

Neodymium and praseodymium have nice colors in their ionic compounds, but their aqueous chemistry is confined to the +3 oxidation state.

Actually, compared to the transition metals, the chemistry of the lanthanoids is not that interesting. Really interesting chemistry is obtained for vanadium, chromium, molybdenum and copper, with numerous colors, complexes and extensive redox chemistry.

Iridium is another very interesting one, but it is soooooo expensive.

I am a fish - 8-10-2007 at 09:15

Quote:

Originally posted by Sauron
I think you mean lanthanides not lanthanoids.

Please stop bossing other people around, especially when it concerns trivia. Lanthanoid is a perfectly valid (though lesser used term), which returns nearly 5000 hits on Google Scholar.

Now can we get back to discussing lanthanoid chemistry...

Sauron - 8-10-2007 at 10:04

I was not "bossing anyone around."

Do not mischaractarize what I posted.

I was correcting what I thought was a mistake. It was not a mistake, merely a post-2003 vogue that has not caught on, and I do NOT care how many hits it has in Google Scholar. That is not a measure of reality.

LANTHANIDE has a long and illustrious history of usage, whereas lanthanoid is a four year old johnny come lately.

Antwain - 8-10-2007 at 15:20

It is a moot point. You all knew what I meant. The main reason I put it in is because the FSE - ie. the one we are supposed to use before posting - is frankly crap, and I figured that including that may help it show up if anyone is interested in the future.

Yes indeed, lets get back to the topic at hand. Cotton and Wilkinson has some information on the metals and salts of these elements, but it is a far to theoretically oriented book for use in this case. None of my other books mention them except briefly. Are there any brightly coloured or for any other reason interesting compounds that can be made with these elements. I am sure that some of you must have made stuff.

PS. IUPAC can go to hell for all I care, all that matters when discussing chemistry is that one can communicate clearly. If people know unambiguously what you are talking about, then it is right. This was a major sticking point when I first became interested in chemistry in yr 10. They INSISTED that we call acetic acid "ethanoic acid" but I had already become attached to the only name it is ever known by. After raising a stink when I was marked incorrect I dragged in several random papers and they were forced to concede. (BTW the spell checker doesn't like "ethanoic" either

)

Sauron - 8-10-2007 at 23:34

IUPAC has its place, but I agree with you that acetic acid is a fine name and I doubt that ethanoic acid will ever displace it.

And yes the FSE is mostly useless.

12AX7 - 9-10-2007 at 04:15

My organic chem prof says "1-methylethyl" is the 'preferred' systematic name, but nobody ever uses anything other than "isopropyl"...

And let's not forget the spoken confusion of -ane, -ene, -yne and -ine.

Tim

Sauron - 9-10-2007 at 04:51

Let's not forget 2-propyl. Same as isopropyl or (shudder) 1-methylethyl.

Antwain - 9-10-2007 at 05:39

so about those rare earths......

Can someone at least tell me where to find some good but general (ie. not an obscure research parer) online lit about them?

not_important - 9-10-2007 at 06:41

I've picked up various books on the REE (lanthanides is so new wave) over the years. Most of those from the 40s and earlier 50s focus on the separation, often in the context of nuclear research. The 50s and 60 tended to be alloys, later 60s on had a lot on phosphors using REE as doping elements. More recent ones have more on coordination complexes and organic chemistry, neither of which are really home lab stuff unless you've a high field NMR or can do work in an oxygen free atmosphere.

Cerium has the most interesting inorganic chemistry, because it is easy to schlep it between Ce(III) and Ce(IV), and the Ce(IV) compounds are coloured. Eu has the Eu(II) state, which can be obtained fairly simply, but the chemistry of Eu(II) is pretty similar to barium.

these two overviews pretty much sums it up
http://www.chem.ox.ac.uk/icl/heyes/LanthAct/L7.html

http://library.lanl.gov/cgi-bin/getfile?rc000021.pdf

After that try Google books limiting the search to "full view" and using "rare earths" or specific element names.

You might find the <i>Clay Times</i> "Fluorescent Glazes" (Jon Singer), 2005 May/Jun:48-52 interesting.

Engager - 11-10-2007 at 18:06

Most of metalls from this group can be made by reacting corresponding flouride with metallic calcium in vacuum at high temperatures. I got my thullium (Tm) sample using this method. I have samples of pure metallic neodymium, sammarium, thullium, lanthanum, cerrium, gadolinium and yttrium. I can post photos of them if you want.

My favourite sample is gadolinium, it's ferromagnetic below 16C and paramagnetic above this temperature. You can see magnetic transition point transformation effects around room temperature.

Antwain - 11-10-2007 at 19:56

Surely unless you obtained a bunch of stuff for free, the cost of TmF3 + calcium metal would be greater than simply buying the metal to start with.

Interesting that gadolinium does that. All the more so because 2 weeks ago I would not have actually understood how that can happen. I was hoping that my 'condensed matter physics' course would be good for something.

JohnWW - 12-10-2007 at 03:07

Because it has 7 unpaired 4f electrons, in addition to an unpaired 5d electron, in the ground state, which are the maximum possible numbers of unpaired electrons, gadolinium (and similarly curium), should theoretically be the most strongly ferromagnetic pure metals. However, I am surprised that it loses its ferromagnetism at only 16ºC.

[Edited on 12-10-07 by JohnWW]

Jdurg - 19-10-2007 at 16:46

With regards to the Lanthanide/Lanthanoid nomenclature, I fully agree with IUPAC stating that Lanthanoid is the proper nomenclature here. The biggest mistake you can make when working with chemicals is assume something, and if someone says that they are studying Lanthanide Chemistry how can you be certain that they are talking about the Lanthanoid elements, or just Lanthanum's negatively charged ions?

I took chemistry back in the mid 1990's in high school, and even back then I learned to call them Lanthanoids and Actinoids since the -ide nomenclature was seemingly wrong AND confusing. Two things you DON'T want in regards to chemistry.

lantha-whatevers and IUPAC

chemrox - 19-10-2007 at 17:25

While they're at it can someone get IUPAC to suggest the Americans might spell and pronounce"Aluminium" properly?

Antwain - 20-10-2007 at 16:40

@jdurg- don't suppose you mean positively charged ions

I haven't met anyone who cared a toss about the lanthanoids, in general or particular, at uni. If I ever did I would probably interrogate them further once they had expressed their interest, and not be satisfied by "yeah I study lanthanides". I am going to stick with 'its right if people know what you mean. On that not I would wager that I could find an IUPAC named chemical that would take people hours to work out. A picture is worth a thousand IUPAC words.

Jdurg - 20-10-2007 at 16:53

Nah. I'm talking about the negatively charged ones. -ide denotes negative charge so lanthanide would be La-.

12AX7 - 20-10-2007 at 16:57

chemrox: you mean alumium?

(No? Check history on it!)

Antwain - 20-10-2007 at 22:22

Right, I missed that joke completely.

pantone159 - 14-2-2009 at 18:35

Back to the lanthanoids/whatever...

How well do these make the double sulfate "alum" salts like M(I)Ln(III)[SO4]2-xH2O? Some of these varieties are listed in my CRC. I have some lanthanon metals and oxides I could mess with, making some crystals might be fun. Of the ones I have, Pr/Nd/Dy sound like they have the nicest colors.

Sedit - 14-2-2009 at 19:03

chloric1 mentioned a really good source for these rare earth chemicals although he suggested that they are not reagent grades keep in mind that oxides that respectable dealers sell are very pure because they have to perform over and over every time the batch of glaze is mixed and the slightest contamination of any ion will throw the color off sometimes drasticly. I am good freinds with someone that owns a ceramic store and they will tell you that almost every thing they get is 99.999% purity certifyed. If you find a local place that sells the oxides for glazes it will be nothing to have them special order chemicals for you. They are mom and pop organizations most of the time and all it would mean to them is more money in there pocket

~Sedit

PS: Just goes to show I have an order for uranium oxide on the way... so they aint very picky at all

[Edited on 14-2-2009 by Sedit]

DerAlte - 15-2-2009 at 23:20

I know I should nor disinter antique trivia, but Sedit reopened this thread… and I read it. So here goes:
Sauron wrote, way back:

Quote:

Yes, I just found that as well. In this instance I think IUPAC is not serving chemistry well, but, there it is.
Their argument is that the -ide suffix should only be used to denote negative ions.
However, I am an old dog and resist new tricks. It is obvious that all of the traditional chemical names that contain such minor inconsistencies cannot be resolved in such a fashion without creating chaos.
In any case Antwain's periodic chart is merely indulging in a current fashion, it is not incorrect, merely nontraditional.

And

Quote:

LANTHANIDE has a long and illustrious history of usage, whereas lanthanoid is a four year old johnny come lately

The suffix –oid comes from the Greek ‘eidos’ = form, meaning ‘of the same form’, ‘like’. Hence such words as ‘anthropoid’ =’man-like’, ‘arachnoid’ in biology, or ’cycloid’ in mathematics. This usage is ancient (circa 1600s).
The suffix –ide is AFAIK a chemical artifact coined at the time of (maybe by) Lavoisier, and used to indicate ‘a compound with’ ;eg, ‘hydride’, ‘oxide’, ‘peroxide’, dihydride’ etc. There is no necessity for a negative ion, many –ides are covalent.
On the traditional chemical basis a ‘lanthanide’ is a compound with lanthanum. Whereas ‘Lanthanoid’ means like lanthanum. Hence, on good linguistic grounds, it is far preferable. My favorite chemist, Linus Pauling, also uses the term ‘Lanthanon’, to confuse further. This I find too argonic! Like calling Helium a metal! Or there’s Boron, and Silicon…
And while we are on it, aluminum is, of course, correctly, aluminium, as the British have it. Soda --> Sodium; Magnesia --> Magnesium; so Alumina --> Aluminium; because –ium denotes metal.

‘Aluminum’ is like spelling ‘night’ as ‘nite’, except the latter sounds the same – but lacks 700 years of tradition. And, Sauron, what is more traditional than ‘Rare Earths’, even if they aren’t that rare?

Sedit wrote:

Quote:

I am good freinds with someone that owns a ceramic store and they will tell you that almost every thing they get is 99.999% purity certified

Sheer BS, I’m afraid. You’d be lucky to get reagent grade anything.

Der Alte

Sedit - 15-2-2009 at 23:39

No BS you can see the certificates on many of the products that are sold.
Now Im not saying every thing that you will find is that pure but many...many things are.
Some are also just dug from the earth and sold as is also, so one will have to make an inquiry as to whats what.
Granted that they are not made for use in a lab some products are very pure indeed due to the need for consistancy in the glaze colors and more important the ability of the fluxes used in the glazes. The slightest impuritys in some glaze fluxes will be the difference between a job well done or a pile of molten crap on you 2000$ kiln.

Either way other then spliting hairs here it is still worth looking into and most places will be more then happy to special order rare materials for you.

not_important - 16-2-2009 at 03:22

For oxides used to colour glazes in particular, and to a certain extent the glass forming oxides or similar compounds, a reasonable degree of purity is needed to get consistent effects. The major exception is manganese, as it is a strong colourant and generally isn't harmed by some iron..

Rare earths for ceramics often run from 99.5% to 99.999%, with the chief contaminates being the adjacent REE. An example is this supplier http://www.baotou-rareearth.com/nd.html

DerAlte - 18-2-2009 at 22:07

@not_important

I suspect the high quality RE's are only used for laser work. Nd is used for welder's goggles but I doubt purity had to be high for that.

@Sedit

Maybe - I am not a potter or glass expert. Certainly most of the chemicals cannot be relied on to be better than typical reagent grade, often nearer technical which approximately means unknown, chemically.

Cetainly, as not_important says, MnO2 is very impure, often just mined pyrolusite.

Der Alte

Sedit - 19-2-2009 at 11:47

Quote:

Originally posted by DerAlte
Certainly most of the chemicals cannot be relied on to be better than typical reagent grade, often nearer technical which approximately means unknown, chemically.

Yes just blindly realying on it being pure is not a good idea but you can get certification from the distributer giving the chemical composition of substances. One thing about ceramic industry is the more common the material the less pure its going to be. Such as the MnO for instance or products like Gerstley Borate which went out of production because the mine closed up IIRC. Common materials are just dug out of the ground and sold as is based on the composition it came out as. Incidently I remeber the struggle people had trying to reproduce the formula for Gerstley Borate until manufactures started reproducing the mixture.

But back on topic since what where looking for are rare earth materials and the ceramic, glass, and super conductor industrys are still running test with them you can get high purity with little searching.I remeber while taking my classes we had giant bags of MnO and borates but a relativly small jar of Barium carbonate that was 99.999% pure(Which they threw out and wouldnt let me have :mad: