Chemists have been doing computations for centuries, but the field we know today as “computational chemistry” is a product of the digital age. Martin Karplus, Michael Levitt, and Arieh Warshel won the 2013 Nobel Prize in Chemistry for work that they did in the 1970s, laying the foundations for today's computer models that combine principles of classical (Newtonian) physics and quantum physics to better replicate the fine details of chemical processes. In 1995, three computational chemists, Paul Crutzen, Mario Molina, and F. Sherwood Rowland, won the Chemistry Nobel for constructing mathematical models that used thermodynamic and chemical laws to explain how ozone forms and decomposes in the atmosphere. However, computational chemistry was not generally thought of as its own distinct field of study until 1998, when Walter Kohn and John Pople won the Chemistry Nobel for their work on density functional theory and computational methods in quantum chemistry.
Computational chemists' daily work influences our understanding of the way the world works, helps manufacturers design more productive and efficient processes, characterizes new compounds and materials, and helps other researchers extract useful knowledge from mountains of data. Computational chemistry is also used to study the fundamental properties of atoms, molecules, and chemical reactions, using quantum mechanics and thermodynamics.
Computational chemists use mathematical algorithms, statistics, and large databases to integrate chemical theory and modeling with experimental observations. Some computational chemists create models and simulations of physical processes, and others use statistics and data analysis techniques to extract useful information from large bodies of data. Advances in computer visualization capabilities make it possible for the computational chemist to present complex analyses in a readily understandable form, which they can use to design experiments and new materials and validate the results.
Computational chemists may use simulations to identify sites on protein molecules that are most likely to bind a new drug molecule or create models of synthesis reactions to demonstrate the effects of kinetics and thermodynamics on the amount and kinds of products. They can also explore the basic physical processes underlying phenomena such as superconductivity, energy storage, corrosion, or phase changes.
The pharmaceutical industry, a major employer of computational chemists, has historically focused on the discovery and design of new small-molecular therapeutics. Recently, however, there is a trend to apply computational chemistry and cheminformatics (a field that combines laboratory data, chemical modeling, and information science methods) to process development, analytical chemistry, and biologics (medicinal products manufactured using or extracted from biological sources).
Computational chemists may use high-performance computing (supercomputers and computing clusters) to solve problems and create simulations that require massive amounts of data. Tools of computational chemists include electronic structure methods, molecular dynamics simulations, quantitative structure–activity relationships, cheminformatics, and full statistical analysis.
Computational chemistry is not the same as computer science, although professionals in the two fields commonly collaborate. Computer scientists devote their time to developing and validating computer algorithms, software and hardware products, and data visualization capabilities. Computational chemists work with laboratory and theoretical scientists to apply these capabilities to modeling and simulation, data analysis, and visualization to support their research efforts.
Many computational chemists develop and apply computer codes and algorithms, although practicing computational chemists can have rewarding careers without working on code development. Programming skills include compiling FORTRAN or C code, performing shell scripting with bash, Tcl/Tk, python, or perl, performing statistical analysis using R or SPSS, and working within a Windows, MacOS, or Linux environment.
As cheminformatics tools and computational modeling platforms develop, it becomes easier to define workflow tasks through graphically based workbench environments. A recent trend in reduced-order modeling and similar methods is enabling fairly powerful computational tools to be implemented on portable devices, including tablets and smart phones. This enables researchers to perform what-if calculations and try out various scenarios while they are in the plant or out in the field.
Typical work duties include the following:
Computational chemists require a solid background in chemistry or a related scientific field, along with computer training. A familiarity with chemical principles, including conformational analysis, acid–base equilibria, physical organic chemistry, molecular structure, thermodynamics, and stereochemistry is necessary for selecting and applying computational tools effectively and performing an insightful analysis of the results.
Research positions usually require a Ph.D. and additional experience in a field of specialization such as pharmaceuticals, structural biology, geosciences, materials science, or physics. This cross-disciplinary background is especially helpful when collaborating with colleagues in experimental research.
Research associates may have master's degrees and some experience, although opportunities for entry and advancement are limited for those without Ph.D. degrees. Master's-level scientists may do software and hardware maintenance. They may also support and train users and customers, which requires practical experience gained on the job, in addition to a strong academic foundation. Jobs that focus on chemical engineering or software programming and architecture sometimes accept practical experience in lieu of a doctoral degree.
A knowledge of the basic aspects of several programming languages helps computational chemists to collaborate effectively with computer scientists who typically bear the main responsibility for developing computer algorithms and software architectures. Computational chemists learn the strengths and weaknesses of various types of software and mathematical tools, and they can identify the best tools to use for a particular kind of problem. They must also be able to interpret the results of a calculation or simulation and evaluate whether the results accurately represent physical reality.
Licenses are not generally required for computational chemistry.
Computational chemists working at government agencies or national laboratories may be required to undergo background checks or obtain security clearances, based on the nature of the work and the security requirements of the laboratory.
Computational chemists may work in a laboratory, in addition to working on computational projects. Often, a laboratory chemist will have some expertise in using modeling, simulation, and statistical analysis to assist in guiding experiments and interpreting the results. Most computational chemists work full time, and many of them have flexible work schedules.
Some computational chemists work exclusively on developing and applying software. They collaborate with their colleagues in the laboratory, clinic, or field to apply and validate their models. They may also work with computer scientists who develop advanced hardware and software capabilities for working on especially large or complex problems.
Smaller companies and academic departments often require a computational chemist to be able to run every aspect of the computational work, from hardware and software maintenance to application of modeling techniques. At larger institutions, groups tend to have individual experts in software development, hardware maintenance, system administration, and modeling applications.
Computational chemists may be required to train others in data collection and analysis methods, software packages, and computer visualization capabilities. They may participate in consortia to develop and apply new capabilities and establish the reliability and accuracy standards necessary for bringing a new software tool to a broader user community. They may also make presentations at conferences or conduct workshops.
Computational chemists in academic environments often teach courses or provide individualized instruction on using various types of software or data analysis. At national laboratories, they may train visiting users, and they may perform their own research. Customer service computational chemists may travel to their customers' laboratories to provide them with training or technical assistance.
Job opportunities in industry include companies in the pharmaceutical, petroleum, and chemical industries. Government jobs are available at the national laboratories and various government agencies.
Graduates with master's degrees can sometimes find employment as research associates or in user support roles; however, the number of positions and opportunities for advancement are limited without a Ph.D. Students or recent graduates with an interest in research may do one or more internships in preparation for selecting an area of specialization for a graduate degree.
Research and supervisory positions generally require a doctoral degree, often with several years of postgraduate experience. Postdoctoral fellowships are one way to gain this experience, although this is not an absolute requirement.
Professional-level computational chemists may pursue a teaching and/or research career in academia, or they may work in industry or for a government agency or national laboratory. They may also support and train facility users, students, or customers or develop new capabilities for collecting and analyzing data.
After gaining several years of postgraduate experience, computational chemists may move into program management or administration, or they may lead teams of researchers working on a large project.
The U.S. Bureau of Labor Statistics predicts a 15% increase in the number of “computer and information research scientists” (a category that includes computer scientists as well as computational scientists) between 2012 (26,700 jobs) and 2022 (30,800 jobs). This is a faster increase than the average for all jobs.
ChemCensus 2010 lists the number of chemists working in industry who describe their primary work function as “computer programming/analysis/design,” which may include duties other than computational chemistry. The number of respondents in this category whose highest degree is a B.S. grew from 42,200 in 1990 to 100,000 in 2010. The number with M.S. degrees grew from 48,800 in 1990 to 96,000 in 2010. The number with Ph.D. degrees grew from 55,200 in 1990 to 109,500 in 2010.
A computational chemist must understand the underlying principles of a simulation, optimization, or other calculation to set up the conditions and parameters and to ensure that the results are meaningful and properly interpreted. Computers can create 3D models of molecular structures, but an ability to correlate these structures with properties of the material requires an ability to visualize and interpret these models. This requires patience, logical thinking, and attention to detail.
Computational chemists collaborate with synthetic and analytical chemists, and often, they must have some degree of expertise across several disciplines. They may be required to adapt and create new software capabilities to handle unusual or difficult problems, and they must stay current on emerging hardware and software capabilities.
Computational chemists are often asked to help explain results or predict outcomes of experiments. Thus, the successful application of calculations requires computational chemists to understand the problem that their customers or colleagues are trying to solve, and to influence their decisions on the types of experiments they perform. A strong social background helps computational scientists develop the strong communications skills, outgoing nature, and advisory role they will need in order to be successful.
Any company with an active R&D effort or a need to optimize processes and characterize products is a potential employer of computational chemists.
Obtaining a degree in computational chemistry can enable a career transition into other fields such as financial modeling or the modeling and interpretation of “big data.”
A significant majority of computational chemistry positions require a Ph.D. and often one or more postdoctoral fellowships or several years of workplace experience.
A limited number of positions that do not require Ph.D. degrees are available for scientific programmers and engineers, software and hardware maintenance staff, and customer/user support staff.