Now, spin decoupling and field lock for the Perkin-Elmer Model R-24 NMR Spectrometer.

The introduction of our Model R-24 was a significant breakthrough in NMR spectroscopy. It provided high resolution and high quality performance plus pushbutton sim­plicity for under $12,000.

The R-24 was an instant suc­cess, indicating how well it fit the needs of modern laboratories.

Now, we've improved on the R-24. To its proven reliability and accuracy we've added an important option: Spin Decoupling and Dy­namic Lock.

Partial spectrum of crotonaldehyde showing the olefinic region decoupled (A) and undecoupled (B) by irradiation of the sample at the methyl frequency.

This gives you greater stability in all environments and makes in­terpretation of complex molecule spectra far easier. Shown in the chart is an example of the super­lative performance of the Decoup­ling and Dynamic Lock feature.

But there's more. The Model R-24 also has the highest integra­tion accuracy of any instrument in its price class. It's been increased from 5% to a guaranteed 2.5% as measured on a 5% ethylbenzene solution. (And the R-24's integral precision is even better than its accuracy!)

The Perkin-Elmer Model R-24 operates at 60 MHz to provide data in a form directly comparable to most published NMR reference spectra. And it has better than 50% improvement in its S/N, making possible precise analyses with only 200 μ\ of sample solution — about half of that required by most other NMR spectrometers.

And here's good news for pres­ent owners of the Model R-24. Your instrument can easily be retro-fitted with the Spin Decoupling and Dy­namic Lock accessory. Just ask us.

For details, write the Instrument Division, Perkin-Elmer Corp., 702 Main Avenue, Norwalk, Conn. 06856.

PERKIN-ELMER CIRCLE 171 ON READER SERVICE CARD

ANALYTICAL CHEMISTRY, VOL. 44 , NO. 13, NOVEMBER 1972 · 7 1 A