🚀 go-pugleaf

nuke@reed.edu (Bill Newcomb) writes:
: laurent@cenerg.cma.f writes:
: >Some studies have been carried out on X ray characterization
: >of C60 cristal:
: 
: >1 - What does an X ray diffraction spectrum of C60 cristal
: >look like ?
: 
: A bunch of dots, I'm sure. Almost all diffraction patterns do (well,
: powder patters look like a bunch of circles, but I assume you mean single
: crystal). It's somewhat straightforward to get the structure from that dot
: pattern, but only very rough features can be gotten from jsut looking at
: the pattern. 
: 
: >2 - Because caracteristic dimension of the cristal grid is 
: >about 10 nm why using X ray ? Wouldn't it be better 
: >to use greater wave length ?

: 
: You might use 10nm light if you only wanted to know how the speres were
: packed. With x-rays, you stand a good chance of being able to tell where
: individual atoms are, thus gaining a great deal of information. 
: 

But I read in papers that C60 cristal was not a real cristal 
but a "molecular cristal" in the sense that every buckyball
(at non zero temperature) is moving arround the sphere center with 
a random movement (no covalent link between atoms of two buckyball).
So how to be able to tell where individual atoms are ?



: It'd be neat to see an ortep diagram of the ball.
: 
: Bill Newcomb
: 
: --
: ~/.oo

--
======================================================
| Laurent Fulcheri          |TEL :  (33) 93 95 74 06 |
| Centre d Energetique      |                        |
| Ecole des Mines de Paris  |FAX :  (33) 93 95 75 35 |
| Rue Claude Daunesse       |========================|
|                           |                        |
| 06560 SOPHIA ANTIPOLIS    | laurent@cenerg.cma.fr  |                      |
| FRANCE                    |                        |
|=====================================================