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[交流] 【求助】按照ICSD的数据在MS中建模遇到原子相距太近怎么处理?已有6人参与

建模过程:进入MS-Build-Crystals-选择点群-输入晶格参数-输入原子位置(这里是一个Mn原子位置,两个O原子位置)

问题:
(1)相临O原子之间的间隔非常小(~0.5 Angstrom),这样的晶体结构是"好"的晶体吗?
(2)这样的模型可以作为输入结构来计算吗?

根据后面所附的ICSD建的模型如下:

ICSD数据如下:
*data for ICSD #78331
CopyRight ?2005 by Fachinformationszentrum Karlsruhe, and the U.S. Secretary of
         Commerce on behalf of the United States.  All rights reserved.
Coll Code 78331
Rec  Date 1996/04/22
Mod  Date 1999/01/19
Chem Name Manganese Oxide - Gamma
Structured  Mn O2
Sum       Mn1 O2
ANX       AX2
Min Name Ramsdellite
D(calc)    4.88
Title    A powder neutron diffraction study of lambda and gamma manganese
         dioxide and of Li Mn2 O4
Author(s) Fong, C.;Kennedy, B.J.;Elcombe, M.M.
Reference Zeitschrift fuer Kristallographie (149,1979-)
         (1994), 209, 941-945
Unit Cell 9.3229(11) 4.4533(7) 2.8482(3) 90. 90. 90.
Vol       118.25
Z          4
Space Group P n a m
SG       PNAM
SG Number 62
Cryst Sys orthorhombic
Laue Class  mmm
Pearson    oP12
Wyckoff    c3
R Value    .0427
Symmetry    1          x+.5, -y+.5, z
            2          x, y, -z+.5
            3          -x+.5, y+.5, z+.5
            4          -x, -y, -z
            5          -x+.5, y+.5, -z
            6          -x, -y, z+.5
            7          x+.5, -y+.5, -z+.5
            8          x, y, z
Red Cell P  2.848 4.453 9.322 90 89.999 89.999 118.251
Trans Red 0.000 0.000 -1.000 / 0.000 1.000 0.000 / 1.000 0.000 0.000
Comments PDF 44-142. R(Bragg)=0.0134
         Compound with mineral name: Ramsdellite
         Neutron diffraction (powder)
         The structure has been assigned a PDF number: 44-142.
         Rietveld profile refinement applied
         Calculated density unusual but tolerable.
Atom  # OX SITE    x          y          z          SOF    H       ITF(U)
Mn 1  +4 4 c 0.1203(15)  0.0130(33)  0.25          1.       0             0
O 1  -2 4 c 0.0356(15)  0.2311(15)  0.75          1.       0       0.025(3)
O 2  -2 4 c 0.2842(12)  0.2934(20)  0.25          1.       0             0
Lbl  Type    U11       U22       U33       U12       U13       U23
Mn1  Mn4+ 0.020(4) 0.029(5) 0.017(3) 0.013(4) 0          0
O2 O2-  0.006(3) 0.050(5) 0.008(3) -.027(3) 0          0
*end for ICSD #78331

[ Last edited by cenwanglai on 2010-6-3 at 22:49 ]

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