Sciencemadness Discussion Board

Old IR Spec Equipment

Flip - 22-6-2006 at 18:45

I'm in the market for used IR units, but i'm wondering...

What is the average shelf life of an IR spectrometer?
(Assume it's lived it's life in a professional lab, not uni)

I have noticed the prices varying wildly, sometimes even on the same model, and i'm trying to get a handle on the market. It's extremely hard to draw a correllation between the price of the new unit, and the various asking prices. Any general advice on the spectroscopy aftermarket would be *extremely* appreciated.

[Edited on 6/23/06 by Flip]

unionised - 23-6-2006 at 00:35

We got a new one in about 1992, it's still running well. It replaced one that was old enough to keep it's software backups on punched tape. I'm guessing about 1975 -1980. That gives a "half life" of about 15 years.
Of course there's a limit to what you can read into 2 data points.

What do you want one for?

virgil - 25-6-2006 at 03:58

There are two types of IR Spectrophotometers - Dispersive and FTIR. The dispersive type uses a prism and diffraction grating that has to be mechanically positioned to isolate the wavelengths with slits and such. The FTIR is a more modern instrument that uses a filament to simultaneously generate all wavelengths of interest and then utilizes the Fourier Transform to resolve the individual wavelengths, thus generating the spectrum. Both are rugged instruments that can last indefinitely.

I am assuming that you are in the market for a FTIR instrument, pre-owned. The wide difference that you noticed in price is due to the different manufacturers' philosophies. Perkin-Elmer sold a good instrument, but refuses to give out maintenance information except on a case-by-case basis. I know this because we have a PE Paragon 500 that I had to repair recently. The filament had burned out.

Nicolet, on the other hand, offers a slightly higher-priced instrument that comes with beautiful manuals.

Both types need to have desiccant in the SEALED light path in order to prevent the water peak from being too huge to subtract. If you are buying from on-line auctions remember the old warning "Caveat Emptor" - "Let the buyer beware."

neutrino - 25-6-2006 at 07:52

My lab has a cheapo ($10k) Nicolet FT-IR that was bought (brand new) because of certain budget issues. Put simply, this thing is a piece of shit. It routinely gives >1000% transmittance, ZnSe reflectance barely works at all, etc. etc. If you're looking for something, avoid the cheap Nicolets.

unionised - 26-6-2006 at 11:07

The one we got rid of was a Nicolet and it was a pig (and it certainly wasn't cheap).

Flip - 27-6-2006 at 01:36

Anybody have any experience with the Nicolet Magna? I'm looking at one right now in a government surplus auction, and it looks like it's a steal.

vulture - 27-6-2006 at 12:27

If you get an FTIR spectrometer you better make sure you get the software with it. Otherwise it's pretty damn useless as the PC does the interpretation.

hinz - 30-6-2006 at 13:56

Does anyone have some experience with a Nicolet 510? Maybe I'm buying one and I like to know how accurate it is or if it's some of those "pieces of shit"? I know it's one of the most used FT-IR types, so I think it should be good.
Does any universal software for IR-spectrometry exist or does every type use it's own software?
How useful are IR-microscopes in analytical organic chemistry?

unionised - 1-7-2006 at 05:26

"How useful are IR-microscopes in analytical organic chemistry? "
Good enough that they still sell in spite of the price tag. Personally I would trade in my grandmother for one.

(Actually that's not as cruel as it seems - she's been dead for 20 years but I'm sure you get the idea; a really nice toy to have).