24小时热门版块排行榜

返回列表

longwei1221

铁虫 (小有名气)

应助: 1 (幼儿园)
金币: 116.8
散金: 128
红花: 20
帖子: 191
在线: 81.7小时
虫号: 1439584
注册: 2011-10-12
性别: GG
专业: 核技术及其应用

[求助] ICSD一些数据的意义请教

*data for ICSD #41492
Coll Code 41492
Rec  Date 2002/04/01
Mod  Date 2005/10/01
Chem Name Beryllium Fluoride
Structured  Be F2
Sum       Be1 F2
ANX       AX2
D(calc)    2.37（这里是什么意思？代表晶包的距离吗？单位是埃么？）
Title    Crystal-structure calculations with distorted ions
Author(s) Lacks, D.J.;Gordon, R.G.
Reference Physical Review, Serie 3. B - Condensed Matter (18,1978-)
         (1993), 48, 2889-2908
Unit Cell 4.688 4.688 5.185 90. 90. 120. (是在MS输入中添加原子时候的a b c和三个角度信息吗？)Vol       98.69
Z          3
Space Group P 31 2 1
SG Number 152
Cryst Sys trigonal/rhombohedral
Pearson    hP9
Wyckoff    c a
Red Cell P  4.688 4.688 5.185 90 90 120 98.686
Trans Red 1.000 0.000 0.000 / 0.000 1.000 0.000 / 0.000 0.000 1.000
Comments Origin shift of .3333 along c-axis.
         PEG model (polarization-included electron gas)
         Measured cell: 4.740, 5.150, quartz-type, stable up to 493
         K
         The structure has been assigned a PDF number (calculated
         powder diffraction data): 01-070-2555
         The structure has been assigned a PDF number (experimental
         powder diffraction data): 13-171
         Structure calculated theoretically
         Structure type : Quartz,low
         X-ray diffraction from single crystal
         No R value given in the paper.
         At least one temperature factor missing in the paper.
Atom  # OX SITE    x          y          z          SOF    H
Be 1  +2 3 a 0.47       0          0.3333       1.       0
F 1  -1 6 c 0.419    0.269    0.213       1.       0
（这里Be和F的xyz是添加原子时候各自的a b c吗？为什么同样的BeF2有那么多中不同的结构？空间群都不同？）*end for ICSD #41492

对于BeF2好像有很多不同的数据，几乎完全不同结构，而且大部分都是常温下的，这个怎么讲呢？实际氟化铍晶体难道真有这么多中类型？据我所知也就一种而已啊，希望高手解答一下！

回复此楼