Computer monitors, lasers and suntan lotions have more in common than you might think.

All of these products take advantage of photochemistry, reactions that occur when matter, or molecules, react with light. An understanding of how these reactions proceed can lead to even better lasers, computer monitors and sunscreens, said Texas A&M University chemist Jaan Laane.

Light is a form of energy. When matter absorbs particles of light, called photons, the molecules become "excited" and change their molecular shapes and structures. The chemical properties of the molecules also change as the molecules fall apart and change their atomic structures or become more reactive.

Photochemical reactions are common in nature. Photosynthesis, the process by which plants make their own food, is an example of a photochemical reaction that occurs when chlorophyll in plants absorbs light from the sun.

The formation of smog in the atmosphere is another common photochemical reaction. Sunlight reacts with atmospheric pollutants such as nitrogen oxides and sulfur dioxide, which fall apart or rearrange themselves and react again to produce ozone, the primary ingredient of smog.

Laane's experiments use lasers to emit ultraviolet (UV) light that then excites the molecules being studied.

"After we excite them with ultraviolet laser light, " Laane said, "we examine in great detail what the structures and properties of these excited molecules are."

The goal of this research is to learn exactly how these reactions proceed and how particular molecules change when they absorb light. This basic knowledge, Laane said, provides insight into how photochemical processes work on a fundamental level and why molecules, normal or excited, have the shapes and structures they do. And, as most chemists agree, understanding molecular shapes and structures explains nearly all chemistry.

Laane's research is partially funded by the Houston-based Welch Foundation and has been for 30 years. He has received 10 three-year grants from the foundation since 1970.

Founded in 1954 by oilman Robert A. Welch, the foundation supports basic chemistry research in Texas institutions. This year 34 Texas A&M University chemists, biochemists and medical researchers, including Laane, received over $4.7 million from the Welch Foundation to continue their research projects. Each three-year grant provides a minimum of $135,000 to support the research of full-time, tenured and tenure-track faculty members.

The Welch Foundation has done a great deal to advance chemical research in Texas, Laane said.

Contact: Lesley V. Kriewald, (979) 845-4646, lvk@univrel.tamu.edu, or Dr. Jaan Laane, (979) 845-3352.

Office of University Relations
Texas A&M University
(979) 845-4641

Kriewald Leslie

College of Science
517 Blocker
TAMU 3257 | 979-845-7361
Site Policies
Contact Webmaster
Social Media