We've made 24 complex improvements in our newest NMR system, not the least of which makes it easier to operate.
In the 20 years we've spent learning about N M R spectroscopy, one of the things we've learned is that it's hard enough to get good spectra w i t h o u t having to fight your instrument, too. That's why we're especially proud to i n t r o d u c e t h e n e w Varian X L - 1 0 0 h i g h - r e s o l u t i o n research system. Because we know N M R , we know that the 100 M H z , 23.5 kG, solid-state XL100 is the easiest to use research N M R spectrometer on the market. And the best designed. But, more importantly, we feel that the XL-100 (using either the standard 12" or new wide-gap 15" high-resolution electromagnet) is the most stable, most sensitive, most versatile N M R system ever built. Like a modern computer, we designed the XL-100 around a fundamental 34 A ·
ANALYTICAL CHEMISTRY
"clock!' In this case, a deuterium mas oscillator operating at 15.4 M H z . And use of a novel f r e q u e n c y division a phase comparator scheme, we've insui that all rf signals in the lock, observi and decoupling channels are absolut synchronous with our master oscillât Next, we built frequency synthesiz into the observing and decoupling ch;
nels and mixed them with the rf sign for h i g h l y a c c u r a t e digital frequen sweeps a n d offsets, w h i l e an opti« encoder in the 10,000 step x-axis dr recorder guarantees perfect registrati between the recorder arm and syntî sizer frequency. T h e n , taking a lesson from our anal ical T-60 spectrometer, we packaged of the XL-100's complex and sophi: cated circuitry into a compact, easyoperate master console. That's the design story of the m XL-100 in a nutshell. Operating featur
)ii the other hand, can't be described as >riefly, but here are some of the more mportant ones: T h e XL-100 provides internal lock on leuterium or protons while observing any mcleus. Deuterium stabilization allows O U to c o n v e n i e n t l y noise d e c o u p l e îydrogen while investigating important luclei such as 1 3 c, 31 p and " B . Furthermore, deuterated solvents are readily available and compatible with most chemical systems you're likely to encounter. T h e rf u n i t g i v e s y o u pushbutton selection of u p to five observing frequencies. By use of additional plug-in rf modules on t h e m a s t e r console u n i t , other nuclei may be accommodated. In order to avoid the spectral overl a p of m o d u l a t i o n s i d e b a n d s a n d usure maximum stability and sensitivity, be XL-100 utilizes single sideband detecion with a fixed modulation frequency of 0.96 k H z which is also coherently genxated from the master oscillator. O u r all-purpose decoupler with xclusive GyroCode® network allows you ο irradiate any nuclear frequency from .-58 M H z and 94-100 M H z for homonulear or heteronuclear decoupling in the yW or noise modulated modes. Of course, he synthesizer in the decoupling channel an also be swept for internuclear double esonance ( I N D O R ) experiments. T h e XL-100's probes increase multim c l e a r f l e x i b i l i t y by i n c o r p o r a t i n g xchangeable pre-amp circuit cards in the ack and analytical channels, as well as he plug-in matching networks for heternuclear double irradiation. And, the >robes used with our 1 5 " wide-gap mag
net permit replacement of the inserts as well. Finally, the new XL-100 system likes any computer you like. It's completely compatible, ready to be interfaced for data processing and/or control functions such as X and Y recorder axes, sweep
widths and offsets, transmitter level or whatever. It's taken 20 years to get to the n e w XL-100. It will take you only a minute to send for complete details. Write Varian, Analytical Instrument Division, 611 H a n s e n Way, Palo Alto, California 94303. Or call ( 4 1 5 ) 326-4000.
( S e e the n e w XL-100 for yourself at the A C S Show, September 7-12. Visit the Varian Working Lab, Booths 3 0 1 313.) varian/analytical instrument division 611 hansen way/palo alto/california 94303/u.s.a.
Circle No. 201 on Readers' Service Card
VOL. 4 1 , NO. 11, SEPTEMBER 1969
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