A proposed modification of CBS-4M model chemistry for application to molecules of increasing molecular size

被引:12
作者
Benassi, R [1 ]
机构
[1] Univ Modena & Reggio E, Dept Chem, I-41100 Modena, Italy
关键词
model chemistry; CBS-4M theory; thermochemistry; sulfur compounds; ab initio molecular orbital methods;
D O I
10.1007/s002140100274
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
In order to calculate more accurately the enthalpies of formation, DeltaH(t)(o)(298 K), for large molecules using the CBS-4M method, a new formulation of the empirical higher-level correction to the energy is proposed: posed: DeltaE = a\S\I-2(ii)ii + b(n(alpha) + n(beta)) + c Delta [S-2] + Sigman(i)d(i). The new methodology (CBS-4MB) applied to a set of 114 molecules of different size significantly decreases the mean absolute deviation from 3.78 to 2.06 kcal/mol.
引用
收藏
页码:259 / 263
页数:5
相关论文
共 14 条
[11]   A complete basis set model chemistry. VI. Use of density functional geometries and frequencies [J].
Montgomery, JA ;
Frisch, MJ ;
Ochterski, JW ;
Petersson, GA .
JOURNAL OF CHEMICAL PHYSICS, 1999, 110 (06) :2822-2827
[12]  
Nicolaides A, 1996, MOL PHYS, V88, P759, DOI 10.1080/00268979609482452
[13]   A complete basis set model chemistry .5. Extensions to six or more heavy atoms [J].
Ochterski, JW ;
Petersson, GA ;
Montgomery, JA .
JOURNAL OF CHEMICAL PHYSICS, 1996, 104 (07) :2598-2619
[14]   Calibration and comparison of the Gaussian-2, complete basis set, and density functional methods for computational thermochemistry [J].
Petersson, GA ;
Malick, DK ;
Wilson, WG ;
Ochterski, JW ;
Montgomery, JA ;
Frisch, MJ .
JOURNAL OF CHEMICAL PHYSICS, 1998, 109 (24) :10570-10579