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tiechong

金虫 (著名写手)

[交流] 【求助】什么软件里含Pariser–Parr–Pople方法? 已有1人参与

有没有什么软件里含Pariser–Parr–Pople method , 在网上找了找,看了几篇用PPP方法计算的文章,都很老了,而且没提到用什么软件的,该不会是手算的?

[ Last edited by yjcmwgk on 2009-11-26 at 13:43 ]
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gzgzgz

铜虫 (小有名气)


小木虫(金币+0.5):给个红包,谢谢回帖交流
一直纠结于ArgusLab没有linux版,无法批量计算。代码在Windows底下超级快。。。500多原子,只要内存够,选10个激发态,70轨道,2小时内完成。
12楼2010-12-16 09:20:58
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yjcmwgk

禁虫 (文坛精英)

密度泛函·小卒

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lei0736(金币+6,VIP+0):谢谢 8-14 08:30
现在流行的化学软件中好像早就没有PPP这个方法了。我见过的最“新”的用PPP方法的一篇文章是1999年的。其实自从TDDFT,CASSCF等方法可以大量快速运行在通用的电脑上之后,谁还用PPP啊。PPP是个半经验方法,甭理他了。

下面援引http://www.chemistrydaily.com/chemistry/Pariser-Parr-Pople_method上面的资料,这个资料也说了,PPP方法是个半经验的方法,半经验方法也忍了,精度又不如zindo这一族,建议你就别费心思找了:

Pariser-Parr-Pople method

The Pariser-Parr-Pople method applies semi-empirical quantum mechanical methods to the quantitative prediction of electronic structures and spectra, in molecules of interest in the field of organic chemistry. Previous methods existed, such as Hückel's rule, but were limited in their scope, application and complexity, as is the Extended Hückel's rule .

This approach was developed in the 1950s by Rudolph Pariser with Robert Parr and co-developed by John Pople. It is essentially a more efficient method of finding reasonable approximations of molecular orbitals, useful in predicting physical and chemical nature of the molecule under study since molecular orbital characteristics have implications with regards to both the basic structure and reactivity of a molecule. This method used a Zero Differential Overlap (ZDO) approximation to reduce the problem to reasonable size and complexity but still required modern solid state computers (as opposed to punch card or vacuum tube systems) before becoming fully useful for molecules larger than benzene.

Originally, Pariser's goal of using this method to predict the characteristics of complex organic dyes, but this was never realized. The method has wide applicability in precise prediction of electronic transitions, particularly lower singlet transitions, and found wide application in theoretical and applied quantum chemistry. The two basic papers on this subject were among the top five chemistry and physics citations reported in ISI, Current Contents 1977 for the period of 1961-1977 with a total of 2450 references.
2楼2009-08-13 13:34:11
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tiechong

金虫 (著名写手)

原来如此,受教了
现在我是想计算一个卟啉铁化合物的pi 电子的, 能不能有什么方法着重在计算pi 电子和pi 电子相关的性质的
3楼2009-08-14 08:20:20
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yjcmwgk

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lei0736(金币+1,VIP+0):谢谢 8-14 09:42
引用回帖:
Originally posted by tiechong at 2009-8-14 08:20:
原来如此,受教了
现在我是想计算一个卟啉铁化合物的pi 电子的, 能不能有什么方法着重在计算pi 电子和pi 电子相关的性质的

你是不是想计算 pi - pi 相互作用?
4楼2009-08-14 09:30:09
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