Anomalous peaks should be doable at shorter wavelengths (if that's all the data there are) as well, depending on data quality. Phaser LLG maps are very sensitive for this. Also by comparing ADPs and local geometry/environment.
JPK -----Original Message----- From: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] On Behalf Of Tim Gruene Sent: Thursday, January 05, 2017 8:38 AM To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] Detecting chlorides in x-tals Dear Reza, if your crystal quality is reasonable, you could collect data at low wavelength and check for the presence of anomalous signal. At Cu Kalpha, f"=0.03 for O and and 0.7 for Cl, at 1.8A, its 0.9A. You might be able to see the anomalous signal for Cl in an anomalous omit map. Best, Tim On Thursday 05 January 2017 01:15:01 PM Reza Khayat wrote: > Hi, > > With the hopes of not reigniting the heated "Chloride or water" CCP4 > discussion in Jan. 2015, what experimental method is suggested for > identifying chlorides in a x-tal? > > Best wishes, > Reza > > Reza Khayat, PhD > Assistant Professor > City College of New York > Department of Chemistry > New York, NY 10031 -- -- Paul Scherrer Institut Dr. Tim Gruene - persoenlich - Principal Investigator Biology and Chemistry OFLC/102 CH-5232 Villigen PSI Phone: +41 (0)56 310 5297 GPG Key ID = A46BEE1A
