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电子理论对话-7:文章是文章,面子是面子
我这里讨论的是科学问题,而不是面子工程。
因此,我只看科学,不看面子。
这回对话的文章,第1作者是我研究生时(85-88年)的同学,第2作者是他的导师余瑞璜先生。当时我搞超塑性(稀土对铝合金超塑性的影响),他跟着余瑞璜搞电子理论。
真是:山不转水转,人不转魔方转。
20年之后,不知道他在搞什么,我却转(魔方)到了余瑞璜的电子理论。
我对话了老同学的文章,如果他看到了,一定会有所反应。因为老乡见老乡还两眼泪汪汪呢,更何况老同学呢!
在这里,我要先告诉他:全国此类事甚多,容当以后统筹解决。
余瑞璜的EET理论是大事,其他都是小事。
文章的作者计算了两种结构:Co2Zr和Fe2Zr,都有错误,错误是一样的,因此,只分析Co2Zr。
原文信息:Co2Zr是立方晶系,晶格常数为6.960埃,空间群为227,晶体学晶胞包含24个原子,8个Zr原子,16个Co原子。
表1 中的数据错了两处,都是把等同键数搞错了。
也许有网友会纳闷,规则是余瑞璜定的,怎么自己会搞错呢?
立法犯法(执法犯法)在日常生活中是家常便饭。
但是,在科学中,一个基本数据的错误,可能导致整个理论不灵。
下面根据余瑞璜定义的等同键数公式,Iα=IM×IS×IK,检验表1 的错误,并且给出满足“自圆其说”的理由。
Co2Zr晶体的空间群表达式为8(8a-Zr)16(16d-Co),
约化到化合式Co2Zr,就是
1Zr2Co=1(8a-Zr)2(16d-Co),得到系数:
IM=1,对于8a-Zr;IM=2,对于16d-Co。
1," ","16d-Co","---","16d-Co"," d===",2.4607
"16d-Co",":",-2.61,-2.61,.87," IS =",6
" SP coordinates=",.125,.125,.625
"16d-Co",":",-2.61,-.87,2.61," IS =",6
" SP coordinates=",.125,.375,.875
Iα=IM×IS×IK=2×6×1=12,等于余瑞璜的结果。
也就是说,余瑞璜也认定IM=2,对于16d-Co。
2," ","8a-Zr","---","16d-Co"," d===",2.8855
"8a-Zr",":",0,0,3.48," IS =",12
" SP coordinates=",.5,.5,1
"16d-Co",":",.87,2.61,2.61," IS =",6
" SP coordinates=",.625,.875,.875
以8a-Zr为参考原子:
Iα=IM×IS×IK=1×12×2=24,等于余瑞璜的结果。
以16d-Co为参考原子:
Iα=IM×IS×IK=2×6×2=24,
这再一次说明,余瑞璜也认定IM=2,对于16d-Co。
3," ","8a-Zr","---","8a-Zr"," d===",3.0138
"8a-Zr",":",1.74,1.74,-1.74," IS =",4
" SP coordinates=",.75,.75,.25
"8a-Zr",":",3.48,3.48,-3.48," IS =",4
" SP coordinates=",1,1,0
Iα=IM×IS×IK=1×4×1=4,等于余瑞璜的结果。
4," ","16d-Co","---","16d-Co"," d===",4.2621
"16d-Co",":",6.09,.87,-.87," IS =",12
" SP coordinates=",1.375,.625,.375
"16d-Co",":",9.57,-.87,-2.61," IS =",12
" SP coordinates=",1.875,.375,.125
Iα=IM×IS×IK=2×12×1=24,不同于余瑞璜的结果(12)。
余瑞璜没有坚持在前面已经认定的IM=2,对于16d-Co。
因此,计算结果是错误的,不满足他自己定义的等同健数的内涵。
5," ","8a-Zr","---","16d-Co"," d===",4.5207
"8a-Zr",":",1.74,1.74,-1.74," IS =",16
" SP coordinates=",.75,.75,.25
"16d-Co",":",2.61,-2.61,-.87," IS =",8
" SP coordinates=",.875,.125,.375
以8a-Zr为参考原子:
Iα=IM×IS×IK=1×16×2=32,不同于余瑞璜的结果(12)。
以16d-Co为参考原子:
Iα=IM×IS×IK=2×8×2=32,
由此可见,必须坚持认定IM=2,对于16d-Co。
才能保证:以键两边原子分别为参考原子,得到结果是一样的。
6," ","8a-Zr","---","8a-Zr"," d===",4.9215
"8a-Zr",":",3.48,-3.48,3.48," IS =",12
" SP coordinates=",1,0,1
"8a-Zr",":",6.96,-3.48,0," IS =",12
" SP coordinates=",1.5,0,.5
Iα=IM×IS×IK=1×12×1=12,等于余瑞璜的结果(12)。
7," ","16d-Co","---","16d-Co"," d===",4.9215
"16d-Co",":",6.09,-.87,.87," IS =",12
" SP coordinates=",1.375,.375,.625
"16d-Co",":",6.09,2.61,-2.61," IS =",12
" SP coordinates=",1.375,.875,.125
Iα=IM×IS×IK=2×12×1=24,等于余瑞璜的结果(24)。
由此可见,余瑞璜定义的等同健数,在求解时需要把晶体学晶胞里的原子数约化到化合式的数目。
即1Zr2Co=1(8a-Zr)2(16d-Co),然后在确定系数:
IM=1,对于8a-Zr;IM=2,对于16d-Co。
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