CheckCIF-PLAT230-260

PLAT230 Type_2 Hirshfeld Rigid-Bond Test (Acta Cryst (1976),A32,239-244

The components of the anisotropic displacement parameters along chemical bonds are assumed to be equal in magnitude. Large differences might indicate contamination of these parameters with other (unresolved) effects such as (substitutional) disorder, model or data errors and/or over-refinement. Atomic sites assigned the wrong scattering type (e.g. Ag versus Br) should generate 'problem signals' with this test. Data sets corrected for absorption effects with DELREF techniques (e.g. DIFABS, SHELXA, XABS2) often show large DELU values for bonds involving the heaviest atom.

Note: The original 'Hirshfeld-test' was defined in absolute terms (see F. L. Hirshfeld, Acta Cryst. (1976). A32, 239-244). The current test is with reference to the associated standard uncertainty.

(http://journals.iucr.org/services/cif/checking/PLAT230.html)

例：PLAT230_ALERT_2_B Hirshfeld Test Diff for C1 - C2 .. 7.53 su

警告原因：上述化学键无法通过刚性键检查。

解决策略：如果仅是个别原子不正常，检查原子类型是否定错，是否需要无序处理，或采用delu(DELU 0.01 0.02 C1 C2)或者isor(ISOR 0.01 0.02 C1 C2)限制精修；如果整体温度因子不正常，检查数据质量是否足够高，或者定错空间群。(DELU限制所指定的原子具有接近指定范围内的位移参数，0.02 0.01必须成倍数关系)。

PLAT231 Type_4 Hirshfeld Rigid-Bond Test (Acta Cryst (1976), A32, 239-244)

The components of the anisotropic displacement parameters along chemical bonds are assumed to be equal in magnitude. Large differences might indicate the contamination of these parameters with other (unresolved) effects such as (substitutional) disorder, model or data errors and/or over-refinement. Atomic sites assigned the wrong scattering type (e.g. Ag versus Br) should generate 'problem signals' with this test. Data sets corrected for absorption effects with DELREF techniques (e.g. DIFABS, SHELXA, XABS2) often show large DELU values for bonds involving the heaviest atom.

Note: The original 'Hirshfeld-test' was defined in absolute terms (see F. L. Hirshfeld, Acta Cryst. (1976). A32, 239-244.). The current test is with reference to the associated standard uncertainty.

(http://journals.iucr.org/services/cif/checking/PLAT231.html)

例：PLAT231_ALERT_4_B Hirshfeld Test (Solvent) P1 -- F2’ .. 9.3 su

警告原因：上述化学键无法通过刚性键检查。

解决策略：如果仅是个别原子不正常，检查原子类型是否定错，是否需要无序处理，或采用delu(DELU 0.01 0.02 P1 F2’)或者isor限制精修；如果整体温度因子不正常，检查数据质量是否足够高，或者定错空间群。(DELU 限制所指定的原子具有接近指定范围内的位移参数，0.02 0.01必须成倍数关系)

PLAT232 Type_2 Hirshfeld Rigid-Bond Test (Metal-X) (Acta Cryst (1976), A32, 239-244)

The components of the anisotropic displacement parameters along chemical bonds are assumed to be equal in magnitude. Large differences might indicate contamination of these parameters with other (unresolved) effects such as (substitutional) disorder, model or data errors and/or over-refinement. Atomic sites assigned the wrong scattering type (e.g. Ag versus Br) should generate 'problem signals' with this test. Data sets corrected for absorption effects with DELREF techniques (e.g. DIFABS, SHELXA, XABS2) often show large DELU values for bonds involving the heaviest atom. A special case are M-C=O type of systems that generally show significant differences for the M-C bond. See D. Braga & T.F. Koetzle (1988), Acta Cryst. B44, 151-155.).

Note: The original 'Hirshfeld-test' was defined in absolute terms (see F. L. Hirshfeld, Acta Cryst. (1976). A32, 239-244.). The current test is with reference to the associated standard uncertainty.

(http://journals.iucr.org/services/cif/checking/PLAT232.html)

例：PLAT232_ALERT_2_B Hirshfeld Test Diff (M-X) Zn -- O1 .. 21.64 su

PLAT232_ALERT_2_B Hirshfeld Test Diff (M-X) Zn -- O2 .. 12.23 su

警告原因：上述化学键无法通过刚性键检查。

解决策略：如果仅是个别原子不正常，检查原子类型是否定错，是否需要无序处理，或采用delu或者isor限制精修；如果整体温度因子不正常，检查数据质量是否足够高，或者定错空间群。

SIMU 0.007 0.001 Zn O1 Zn O2

或者用如下命令，然后精修

EADP Zn O1 Zn O2

PLAT233 Type_4 Hirshfeld Rigid-Bond Test (Metal-X) (Acta Cryst (1976), A32, 239-244)

The components of the anisotropic displacement parameters along chemical bonds are assumed to be equal in magnitude. Large differences might indicate contamination of these parameters with other (unresolved) effects such as (substitutional) disorder, model or data errors and/or over-refinement. Atomic sites assigned the wrong scattering type (e.g. Ag versus Br) should generate 'problem signals' with this test. Data sets corrected for absorption effects with DELREF techniques (e.g. DIFABS, SHELXA, XABS2) often show large DELU values for bonds involving the heaviest atom. Note: The original 'Hirshfeld-test' was defined in absolute terms (see F.L.Hirshfeld, Acta Cryst. (1976). A32, 239-244). The current test is with reference to the associated standard uncertainty.

(http://journals.iucr.org/services/cif/checking/PLAT233.html)

例：PLAT233_ALERT_2_B Hirshfeld Test Diff (M-X) Zn -- O1 .. 21.64 su

PLAT233_ALERT_2_B Hirshfeld Test Diff (M-X) Zn -- O2 .. 12.23 su

警告原因：上述化学键无法通过刚性键检查。

解决策略：如果仅是个别原子不正常，检查原子类型是否定错，是否需要无序处理，或采用delu或者isor限制精修；如果整体温度因子不正常，检查数据质量是否足够高，或者定错空间群。

SIMU 0.007 0.001 Zn O1 Zn O2

或者用如下命令，然后精修

EADP Zn O1 Zn O2

PLAT234 Type_4 Hirshfeld Rigid-Bond Test (Acta Cryst (1976), A32, 239-244)

The components of the anisotropic displacement parameters along chemical bonds are assumed to be equal in magnitude. Large differences might indicate contamination of these parameters with other (unresolved) effects such as (substitutional) disorder, model or data errors and/or over-refinement. Atomic sites assigned the wrong scattering type (e.g. Ag versus Br) should generate 'problem signals' with this test. Data sets corrected for absorption effects with DELREF techniques (e.g. DIFABS, SHELXA, XABS2) often show large DELU values for bonds involving the heaviest atom.

Note: The original 'Hirshfeld-test' was defined in absolute terms (see F. L. Hirshfeld, Acta Cryst. (1976). A32, 239-244.).

(http://journals.iucr.org/services/cif/checking/PLAT234.html)

例：PLAT234_ALERT_4_A Large Hirshfeld Difference C4BA -- C0AA .. 0.32 Ang.

警告原因：上述化学键无法通过刚性键检查。

解决策略：如果仅是个别原子不正常，检查原子类型是否定错，是否需要无序处理，或采用DELU(DELU 0.01 0.02 C4BA C0AA)或者ISOR限制精修；如果整体温度因子不正常，检查数据质量是否足够高，或者定错空间群。(DELU 限制所指定的原子具有接近指定范围内的位移参数，0.02 0.01必须成倍数关系)

PLAT241 Type_2 Test for unusually high U(eq) as compared with bonded neighbors

The U(eq) value of an atom is compared with the average U(eq) for to non-hydrogen atoms bonded to it. Large differences may indicate that the wrong atom type was assigned (e.g. N instead of O).

(http://journals.iucr.org/services/cif/checking/PLAT241.html)

例：PLAT241_ALERT_2_B Low High as Compared to Neighbors for ..... C11

警告原因：某原子同附近原子相比，温度因子较高或者较低。

解决策略：如果仅是个别原子不正常，检查原子类型是否定错，是否需要无序处理，或采用DELU或者ISOR限制精修；如果整体温度因子不正常，检查数据质量是否足够高。

PLAT242 Type_2 Test for Unusually Low U(eq) as compared with bonded neighbors

The U(eq) value of an atom is compared with the average U(eq) for non-hydrogen atoms bonded to it. Large differences may indicate that the wrong atom type was assigned (e.g. N instead of O). False alarms may occur for terminal groups such as the t-butyl moiety.

(http://journals.iucr.org/services/cif/checking/PLAT242.html)

例：PLAT242_ALERT_2_B Low Ueq as Compared to Neighbors for ..... N8

警告原因：某原子同附近原子相比，温度因子较高或者较低。

解决策略：如果仅是个别原子不正常，检查原子类型是否定错，是否需要无序处理，或采用DELU或者ISOR限制精修；如果整体温度因子不正常，检查数据质量是否足够高。

PLAT243 Type_4 Test for unusually high solvent U(eq) as compared with bonded neighbors

The U(eq) value of an atom in the solvent or ion is compared with the average U(eq) for non-hydrogen atoms bonded to it. Large differences may indicate that the wrong atom type was assigned (e.g. N instead of O).

(http://journals.iucr.org/services/cif/checking/PLAT243.html)

警告原因：某原子同附近原子相比，温度因子较高或者较低。

解决策略：如果仅是个别原子不正常，检查原子类型是否定错，是否需要无序处理，或采用DELU或者ISOR限制精修；如果整体温度因子不正常，检查数据质量是否足够高。

PLAT244 Type_4 Test for unusually low solvent U(eq) as compared with bonded neighbors

The U(eq) value of an atom in the solvent or ion is compared with the average U(eq) for non-hydrogen atoms bonded to it. Large differences may indicate that the wrong atom type was assigned (e.g. N instead of O). False alarms may occur for terminal groups such as the t-butyl moiety.

(http://journals.iucr.org/services/cif/checking/PLAT244.html)

警告原因：某原子同附近原子相比，温度因子较高或者较低。

解决策略：如果仅是个别原子不正常，检查原子类型是否定错，是否需要无序处理，或采用DELU或者ISOR限制精修；如果整体温度因子不正常，检查数据质量是否足够高。

PLAT245 Type_2 Test for unusually low H-U(eq) as compared with bonded atom

U(iso) of a hydrogen atom is generally expected to be greater than the U(eq) of the non-hydrogen atom it is attached to.

氢原子的U(iso)的预期值通常比其所连接的非氢原子的U(eq)更大。

(http://journals.iucr.org/services/cif/checking/PLAT245.html)

警告原因：氢原子的U(iso)比其所连接的非氢原子的U(eq)小。

解决策略：一般不会出现，重新加氢并生成CIF文件即可。

PLAT250 Type_2 Test for unusual anisotropic average UIJ

An average value of the U(i,j) tensor of the asymmetric unit of a residue is calculated. An ALERT is generated when the corresponding U3/U1 ratio deviates significantly from 1.0. Large values of this ratio should be taken as an indication of possible systematic errors in the data or errors in the model. Visual inspection of an ORTEP plot will show that many displacement ellipsoids have their major axis pointing in the same direction.

(http://journals.iucr.org/services/cif/checking/PLAT250.html)

警告原因：某原子温度因子热椭球不接近球形，U3和U1方向差值较大。

解决策略：如果仅是个别原子不正常，检查原子类型是否定错，是否需要无序处理，或采用DELU或者ISOR限制精修；如果整体温度因子不正常，检查数据质量是否足够高。

PLAT260 Type__260 .075 0.15 0.20 2 A 0 0 3 0 Test for high average Ueq for residue

A large average Ueq value for a residue may indicate refinement with a too high (possibly fixed) population parameter value.

某残基较大的平均Ueq值可能意味着以过高(可能是固定)总体参数值进行精修。

(http://journals.iucr.org/services/cif/checking/PLAT260.html)

警告原因：某原子温度因子热椭球不接近球形。

解决策略：如果仅是个别原子不正常，检查原子类型是否定错，是否需要无序处理，或采用DELU或者ISOR限制精修；如果整体温度因子不正常，检查数据质量是否足够高。