Molecular modeling graphics

Web connections to many sites related to molecular modeling, graphics, and information... 

In the late 1960s, Langridge and co-workers developed methods, first at Princeton, then at UC San Francisco, to visualize 3D molecular models on the screens of cathode-ray tubes. At the same time Marshall, at Washington University St. Louis, MO, USA, started visuaHzing protein structures on graphics screens. 

Since the early 20th century, chemists have represented molecular information by molecular models. The human brain comprehends these representations of graphical models with 3D relationships more effectively than numerical data of distances and angles in tabular form. Thus, visualization makes complex information accessible to human understanding easily and directly through the use of images. 

New ways to represent structure data became available through molecular modeling by computer-based methods. The birth of interactive computer representation of molecular graphics was in the 196Ds. The first dynamic molecular pictures of small molecules were generated in 1964 by Lcvinthal in the Mathematics and Computation (MAC) project at the Electronic Systems Laboratoiy of the Massachusetts... 

The era of the Evans and Sutherland computer systems vanished in the first half of the 1980s, when powerful and more economical workstations were introduced. In spite of advances in computer graphics and in CPU power, these workstations dominate the everyday life of molecular modeling even today. 

In recent years, the rapid development of low-budget 3D-capablc graphics cards makes it possible to visualize molecular models with standard PC systems. Some molecular modeling software, which was once available only for workstations, is now also offered for PCs [198]. 

Computer graphics has had a dramatic impact upon molecular modelling. It should always be remembered, however, that there is much more to molecular modelling than computer graphics. It is the interaction between molecular graphics and the imderlying theoretical methods that has enhanced the accessibility of molecular modelling methods and assisted the analysis and interpretation of such calculations. 

This German stamp depicts a molecular model of urea and was issued in 1982 to commemorate the bun dredth anniversary of Woh ler s death The computer graphic that opened this in troductory chapter is also a model of urea... 

The graphic that opened this chapter IS a molecular model of phenol that shows its planar structure and electro static potential... 

The use of graphic displays as an essential element of computer-based instmctional systems has been exploited in a number of ways. Molecular modeling and visualization techniques have supplemented the traditional set of stick models in courses on organic and inorganic chemistry, and animation of molecular motion and of the progress or mechanism of chemical reactions has been a useful classroom tool. 

The simulations were carried out on a Silicon Graphics Iris Indigo workstation using the CERIUS molecular modeling and the associated HRTEM module. The multislice simulation technique was applied using the following parameters electron energy 400 kV (lambda = 0.016 A) (aberration coefficient) = 2.7 mm focus value delta/ = 66 nm beam spread = 0.30 mrad. 

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