Recent developments in classical density modification

✍ Scribed by Cowtan, Kevin

• Publisher: International Union of Crystallography
• Year: 2010
• Tongue: English
• Weight: 300 KB
• Volume: 66
• Category: Article
• ISSN: 0907-4449
• DOI: 10.1107/s090744490903947x

✦ Synopsis

Classical density-modification techniques (as opposed to statistical approaches) offer a computationally cheap method for improving phase estimates in order to provide a good electron-density map for model building. The rise of statistical methods has lead to a shift in focus away from the classical approaches; as a result, some recent developments have not made their way into classical density-modification software. This paper describes the application of some recent techniques, including most importantly the use of prior phase information in the likelihood estimation of phase errors within a classical density-modification framework. The resulting software gives significantly better results than comparable classical methods, while remaining nearly two orders of magnitude faster than statistical methods.