Talk:Magnetite

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I'm completely baffled by what the 'chemical formula" section here means, despite my PhD in chemistry. I'm not a geologist, so maybe the terminology makes sense, but can someone check up on this? As far as I understand, the IUPAC name for magnetite should be iron(II,III) oxide (note, there is no space between iron and the parenthesis), and the formula should be written as Fe₃O₄, or at least FeO.Fe₂O₃. I have never seen Fe₂O₂ before! Can someone fix this? I hesitate to do this, in case there is some convention in geology that I'm unaware of. Thanks, Walkerma 14:47, 18 Jan 2005 (UTC)

Done. Where did that come from? No geo convention that I know of. Vsmith 16:22, 18 Jan 2005 (UTC)

Thank you for fixing this- I thought I was going crazy! Walkerma 15:48, 19 Jan 2005 (UTC)

[edit] c.1960, Heinz Lowenstam, Paleoecologist

Animal Magnetism

In the 1960s, Caltech paleoecologist Heinz Lowenstam startled biologists and geologists alike with the discovery that many animals do what conventional science had considered impossible: they manufacture substances such as the iron-containing mineral magnetite within their bodies. Out of Lowenstam's work came the more recent finding that many migratory animals, including birds, bees, and whales, generate magnetite within their bodies and may owe their uncanny homing instincts to the presence of this "internal compass" that allows them to navigate by means of Earth's magnetic field.

Source: http://admissions.caltech.edu/about/milestones/

I though that this might be a nice add to "Biological Occurrences" section, but it is a direct quote from Caltech's website, and may require permission, citation, or both.

HS.1099 07:57, 26 June 2006 (UTC)

The basic info in that quote is already there, but added mention of Lowenstam's work and references for the section. Vsmith 10:55, 26 June 2006 (UTC)

[edit] Ferrous-ferric oxide

I've never seen this compound called by any other name. Magnetite is a geological name, and Fe(II,III) oxide is stock nomenclature. But when anyone names the compound, they say ferrous-ferric oxide (a mixture of ferus and feric oxide). This includes all textbooks I've seen, all students I've talked to, and all teachers who have taught me. One of these teachers is a prefessional research chemist specialising on inorganic reaction mechanism, and he calls it ferrous-ferric oxide. As it is the most common name for the compound, it should be included in the intro. Loom91 14:09, 24 November 2006 (UTC)

Put it back in now that you've corrected the spelling :-) Anyway, the article is about the mineral, chemical discussions would go under an article on the specific chemical. Also note the older -ous, -ic names though still commonly used are not sanctioned by IUPAC. Vsmith 15:18, 24 November 2006 (UTC)

The chemical (a mixture rather than a true compound) does not have a separate article. This article is about the chemical as well as its natural occuring form. Loom91 18:24, 25 November 2006 (UTC)

[edit] Ferro- Ferri- and Magnetite; Plus Misguided notion: "the" chemical

Ferro -- pure parallel coupling of spins + coupling energy beyond critical value + particle not too small --» pure ferromagnet in which DOMAINS, not spins independently, respond to applied fields; spontaneous magnetization at zero applied field; hysteresis, coercive force exist

Super-Paramagnetic -- a would-be ferro, but coupling constant too small (or temperature too high) or particle too small (sub-domain)

Ferri -- two mechanisms, but the the most common is two lattices, one with parallel coupling (ferro) and one with antiparallel coupling (antiferro); magnetite Fe3O4 is a case where Fe3+ ions are in octahedral and tetrahedral sites -- and they couple antiferromagnetically; but Fe2+ ions are in half the octahedral sites too and these Fe2+ couple ferromagnetically; a ferrimagnet is just usually a weaker form of ferromagnet -- all the same phenomenology exists in ferrimagnets that exist in ferromagnets. (Magnetic materials technologists refer to "hard" and "soft" magnetics; but these are just relative magnitudes with no difference in the kind of phenomenology that exists.)

PLEASE E-MAIL ME and I can send you "all" of magnetism explained in two tables: (1) the observed phenomenology for each kind of magnetism and (2) the microscopic mechanism giving rise to each

My e-mail is this: Mark.Weiss@bep.treas.gov

Incidentally, in magnetism -- properties of materials-wise -- it is even insufficient to know the chemical and crystal structure. Real magnetite (synthetic black iron oxide) grades can differ gigantically in terms of magnetic performance. Coercivity could be as little as 40 Oersted for a home-brew to 88 Oersted to 350 Oerseted for commercial syntheses. Squareness, remanence, saturation -- these all vary all over the place, even in commercial grades (purposely even!). So you guys fussing over what to call magnetite don't even realize that there is no "the" identity -- not when it comes to real magnetic properties of real materials. And, by the way, most scientists dealing with magnetism call the stuff magnetite. For that matter, in printing ink, we would call it black iron oxide -- 'cause it's black. It's more important to realize that magnetism is exquisitely sensitive to details at all levels of magnification, than it is to make a debate about what to call "the" chemical. That whole notion of "the" chemical is misguided insofar as magnetism is concerned. I know that this is a kind of cognitive dissonance for most folks -- used to "once I know the compound I know all its chemistry". But magnetochemistry of materials is highly idiosyncratic and the usual chemistry notion of "the" does not apply. Any journal article on magnetic properties of materials will back me up; some even make my statement explicitly. See for instance the journal IEEE Transactions on Magnetics. 199.196.144.11 22:04, 21 March 2007 (UTC)

love you:D —Preceding unsigned comment added by 87.42.135.2 (talk) 12:41, 1 May 2008 (UTC)