CheckCIF-PLAT340-344

PLAT340 Type_3 Check Bond Precision for C-C in Light Atom Structures (Z(max) < 20)

The average s.u. for X-Y bonds is tested (named bond-precision). X-Y will generally be C-C bonds, unless there are none. In the last case the s.u.'s of the lowest element numbers are considered (excluding hydrogen). There are three test ranges: one for structures with the largest element Z < 20, one for the largest Z in the range 20 to 39 and one for structures with Z(max) 40 or higher (_340, _341 and _342 respectively)

(http://journals.iucr.org/services/cif/checking/PLAT340.html)

例：PLAT340_ALERT_3_B Low Bond Precision on C-C Bonds ............... 0.0105 Ang.

警告原因：键误差较大。C-C键精度不够，误差太大。

解决策略：找出有问题的C-C键，限制一下试试。检查精修模型是否正确，是否有末端需要无序处理，晶胞参数误差是否过大。如果均无法解决可尝试收集低温数据。

PLAT341 Type_3 Check Bond Precision for C-C in Structures (19 < Z(max) < 40)

The average s.u. for X-Y bonds is tested (named bond-precision). X-Y will generally be C-C bonds, unless there are none. In the last case the s.u.'s of the lowest element numbers are considered (excluding hydrogen). There are three test ranges: one for structures with the largest element Z < 20, one for the largest Z in the range 20 to 39 and one for structures with Z(max) 40 or higher (_340, _341 and _342 respectively)

(http://journals.iucr.org/services/cif/checking/PLAT341.html)

例：PLAT341_ALERT_3_B Low Bond Precision on C-C Bonds (x 1000) Ang ...

警告原因：键误差较大。C-C键精度不够，误差太大。

解决策略：找出有问题的C-C键，限制一下试试。检查精修模型是否正确，是否有末端需要无序处理，晶胞参数误差是否过大。如果均无法解决可尝试收集低温数据。

PLAT342 Type_3 Check Bond Precision for C-C in Structures (Z(max) > 39)

The average s.u. for X-Y bonds is tested (named bond-precision). X-Y will generally be C-C bonds, unless there are none. In the last case the s.u.'s of the lowest element numbers are considered (excluding hydrogen). There are three test ranges: one for structures with the largest element Z < 20, one for the largest Z in the range 20 to 39 and one for structures with Z(max) 40 or higher (_340, _341 and _342 respectively)

(http://journals.iucr.org/services/cif/checking/PLAT342.html)

例：PLAT342_ALERT_3_B Low Bond Precision on C-C Bonds ...............

警告原因：键误差较大。C-C键精度不够，误差太大。

解决策略：找出有问题的C-C键，限制一下试试。检查精修模型是否正确，是否有末端需要无序处理，晶胞参数误差是否过大。如果均无法解决可尝试收集低温数据。

PLAT343 Type_2 Hybridisation Problem on C in main residue(s)

The angle range is larger than usual for the tentatively assigned hybridisation of the reported atom in the main residue.

主残基中所报告的(碳)原子其初步指认的杂化方式，其角度范围比通常要大。

(http://journals.iucr.org/services/cif/checking/PLAT343.html)

警告原因：结构中某个(或某些)碳原子的几何构型不正常。

解决策略：仔细检查所报告的碳原子的几何构型，检查精修模型是否正确，这些有问题的碳原子是否需要无序处理。

PLAT344 Type_2 Hybridisation Problem on C in solvent/ion

The angle range is larger than usual for the tentatively assigned hybridisation of the reported atom in the solven/anion.

溶剂/阴离子中所报告的(碳)原子其初步指认的杂化方式，其角度范围比通常要大。

(http://journals.iucr.org/services/cif/checking/PLAT344.html)

警告原因：结构中某个(或某些)碳原子的几何构型不正常。

解决策略：仔细检查所报告的碳原子的几何构型，检查精修模型是否正确，这些有问题的碳原子是否需要无序处理。