CheckCIF-PLAT370-380
PLAT370 Type_2 Test for short C3 - C2 (Angstrom Difference) XRAY: 1.31
Large deviations from generally accepted values may indicate model problems, over refinement etc. Default C3-C2 = 1.31 Ang. (X-Ray) value from Ladd & Palmer, Structure Determination by Xray Crystallography (1985).
Note:
- C3-C2 indicates a bond between an atom with 3 bonds and one with 2 bonds.
- Conjugated systems may cause some 'false alarm' messages.
(http://journals.iucr.org/services/cif/checking/PLAT370.html)
警告原因:C(sp2)-C(sp)鍵鍵長(zhǎng)過短。
解決策略:檢查是否需要無序處理,或用DFIX限制距離后精修。
PLAT371 Type_2 Test for long C3 - C2 (Angstrom Difference) XRAY: 1.31
Large deviations from generally accepted values may indicate model problems, over refinement etc. Default C3-C2 = 1.31 Ang. (X-Ray) value from Ladd & Palmer, Structure Determination by Xray Crystallography (1985).
Note:
- C3-C2 indicates a bond between an atom with 3 bonds and one with 2 bonds.
- Conjugated systems may cause some 'false alarm' messages.
(http://journals.iucr.org/services/cif/checking/PLAT371.html)
警告原因:C(sp2)-C(sp)鍵鍵長(zhǎng)過長(zhǎng)。
解決策略:檢查是否需要無序處理,或用DFIX限制距離后精修。
PLAT372 Type_2 Test for short C2 - C2 (Angstrom Difference) XRAY: 1.25
Large deviations from generally accepted values may indicate model problems, over refinement etc. Default C2-C2 = 1.25 Ang. (X-Ray) value from Ladd & Palmer, Structure Determination by Xray Crystallography (1985).
Note:
- C2-C2 indicates a bond between atoms with 2 bonds each.
- Conjugated systems may cause some 'false alarm' messages.
(http://journals.iucr.org/services/cif/checking/PLAT372.html)
警告原因:C(sp)-C(sp)鍵鍵長(zhǎng)過短。
解決策略:檢查是否需要無序處理,或用DFIX限制距離后精修。
PLAT373 Type_2 Test for long C2 - C2 (Angstrom Difference) XRAY: 1.25
Large deviations from generally accepted values may indicate model problems, over refinement etc. Default C2-C2 = 1.25 Ang. (X-Ray) value from Ladd & Palmer, Structure Determination by Xray Crystallography (1985).
Note:
- C2-C2 indicates a bond between atoms with 2 bonds each.
- Conjugated systems may cause some 'false alarm' messages.
(http://journals.iucr.org/services/cif/checking/PLAT373.html)
警告原因:C(sp)-C(sp)鍵鍵長(zhǎng)過長(zhǎng)。
解決策略:檢查是否需要無序處理,或用DFIX限制距離后精修。
PLAT374 Type_2 Test for long N - N Bond (> 1.45 Angstrom)
Large deviations from generally observed bond distances may indicate model problems, over-refinement etc. Check for wrong atom-type assignments. For an example see: Acta Cryst. (2003) E59, m710-m712.
(http://journals.iucr.org/services/cif/checking/PLAT374.html)
警告原因:N-N鍵鍵長(zhǎng)過長(zhǎng)。
解決策略:鍵長(zhǎng)是否原子指認(rèn)錯(cuò)誤,檢查是否需要無序處理,或用DFIX限制距離后精修。
PLAT375 Type_2 Test for C-O-H with large C-O Distance
Strange C-O-H geometry with C-O > 1.45 Angstrom detected. Wrong Atom Type ?
(http://journals.iucr.org/services/cif/checking/PLAT375.html)
警告原因:C-O鍵鍵長(zhǎng)過長(zhǎng)。
解決策略:鍵長(zhǎng)是否原子指認(rèn)錯(cuò)誤,檢查是否需要無序處理,或用DFIX限制距離后精修。
PLAT380 Type_4 Test for incorrectly Oriented Methyl Moiety
This test alerts for possible incorrectly oriented CH3 moieties. (E.g. AFIX 33 instead of AFIX 137 etc. within the SHELXL realm)
(http://journals.iucr.org/services/cif/checking/PLAT380.html)
例:PLAT380_ALERT_4_G Check Incorrectly? Oriented X(sp2)-Methyl Moiety
警告原因:末端甲基AFIX處理方式有錯(cuò)。
解決策略:一般需改成用AFIX 147處理,除非有合理解釋。