Business Notes TECHNOLOGY

They are among the most famous initials in the world, found almost anywhere computers are used. But last week the letters IBM appeared in the pages of the British science journal Nature in an unprecedented form. Two IBM researchers, in a scientific and marketing tour de force, had spelled out their corporate emblem by dragging atoms across a crystal of nickel one at a time. The result: the world's smallest corporate logo, measuring 660 billionths of an inch long.

It was a remarkable demonstration of the precision with which single atoms can now be manipulated, a skill that could conceivably be used someday to build atom-size transistors or to custom-design molecules. Using an instrument called a scanning tunneling microscope and working on a surface chilled to near absolute zero, researchers Donald Eigler and Erhard Schweizer were able to get individual atoms to respond to the magnet-like tug of a fine tungsten needle. But don't expect to see atom-etching booths at your local science fair. It took 22 hours to haul 35 xenon atoms across the bumpy nickel surface. And when the temperature rose above -380 degrees F, the masterpiece flew apart.