Re: [ccp4bb] anomalous signal of Mn and Ca ions

2008-03-01 Thread Nave, C (Colin)
: Re: [ccp4bb] anomalous signal of Mn and Ca ions On Feb 29, 2008, at 10:29, Johan Turkenburg wrote: Hi, You need to firstly check that you did the map calculation correctly, see comments below: Sun Tang wrote: Dear All, In my structures, I want to assign Mn or Ca ions for some densities

Re: [ccp4bb] anomalous signal of Mn and Ca ions

2008-03-01 Thread Andrzej Olczak
February 2008 10:06 To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] anomalous signal of Mn and Ca ions On Feb 29, 2008, at 10:29, Johan Turkenburg wrote: Hi, You need to firstly check that you did the map calculation correctly, see comments below: Sun Tang wrote: Dear All, In my

Re: [ccp4bb] anomalous signal of Mn and Ca ions

2008-02-29 Thread Stephen Graham
As Ethan mentions, your best bet for an 100% positive ID would be to collect a dataset above and below the Mn edge and see the anomalous signal from the Mn atom disappear. If that is not an option, there is a great paper by George Sheldrick and friends regards using the Calcium Bond Valence Sum

Re: [ccp4bb] anomalous signal of Mn and Ca ions

2008-02-29 Thread Johan Turkenburg
Hi, You need to firstly check that you did the map calculation correctly, see comments below: Sun Tang wrote: Dear All, In my structures, I want to assign Mn or Ca ions for some densities. But when I did not have anomalous density in CCP4i. I am not sure whether I was correct. The

Re: [ccp4bb] anomalous signal of Mn and Ca ions

2008-02-29 Thread Anastassis Perrakis
On Feb 29, 2008, at 10:29, Johan Turkenburg wrote: Hi, You need to firstly check that you did the map calculation correctly, see comments below: Sun Tang wrote: Dear All, In my structures, I want to assign Mn or Ca ions for some densities. But when I did not have anomalous density in

[ccp4bb] anomalous signal of Mn and Ca ions

2008-02-28 Thread Sun Tang
Dear All, In my structures, I want to assign Mn or Ca ions for some densities. But when I did not have anomalous density in CCP4i. I am not sure whether I was correct. The following was what I did: I processed the data with HKL2000 and select anomalous signal in scaling. In CCP4i,

Re: [ccp4bb] anomalous signal of Mn and Ca ions

2008-02-28 Thread Ethan A Merritt
On Thursday 28 February 2008 19:54, Sun Tang wrote: Dear All, In my structures, I want to assign Mn or Ca ions for some densities. But when I did not have anomalous density in CCP4i. [snip] I collected the data at the wavelength of 1 A. Mn has only about 1e of anomalous