Ab initio investigation of structure and cohesive energy of crystalline urea

被引:90
作者
Civalleri, B.
Doll, K.
Zicovich-Wilson, C. M.
机构
[1] Univ Turin, Dipartimento Chim, IFM, I-10125 Turin, Italy
[2] Univ Turin, NIS, Ctr Excellence, I-10125 Turin, Italy
[3] Univ Autonoma Estado Morelos, Fac Ciencias, Cuernavaca 62210, Morelos, Mexico
关键词
D O I
10.1021/jp065757c
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
The structure and cohesive energy of crystalline urea have been investigated at the ab initio level of calculation. The performance of different Hamiltonians in dealing with a hydrogen-bonded molecular crystal as crystalline urea is assessed. Detailed calculations carried out by adopting both HF and some of the most popular DFT methods in solid-state chemistry are reported. Local, gradient-corrected, and hybrid functionals have been adopted: SVWN, PW91, PBE, B3LYP, and PBE0. First, a 6-31G(d,p) basis set has been adopted, and then the basis set dependence of computed results has been investigated at the B3LYP level. All calculations were carried out by using a development version of the periodic ab initio code CRYSTAL06, which allows full optimization of lattice parameters and atomic coordinates. With the 6-31G(d,p) basis set, structural features are well reproduced by hybrid methods and GGA. LDA gives lattice parameters and hydrogen-bond distances that are too small relative to experiment, while at the HF level the opposite trend is observed. Results show that hybrid methods are more accurate than HF and both LDA and GGA functionals, with a trend in the computed properties similar to that of hydrogen-bonded molecular complexes. When BSSE and ZPE are taken into account, all methods, except LDA, give computed cohesive energies that are underestimated with respect to the experimental sublimation enthalpy. Dispersion energy, not properly taken into account by DFT methods, plays a crucial role. Such a deficiency also affects dramatically the computed crystalline structure, especially when large basis sets are adopted. We show that this is an artifact due to the BSSE. Indeed, with small basis sets the BSSE gives an extra-binding that compensates for the missing dispersion forces, thus yielding structures in fortuitous agreement with experiment.
引用
收藏
页码:26 / 33
页数:8
相关论文
共 72 条
[1]   Toward chemical accuracy in the computation of NMR shieldings: the PBE0 model [J].
Adamo, C ;
Barone, V .
CHEMICAL PHYSICS LETTERS, 1998, 298 (1-3) :113-119
[2]   van der Waals forces in density functional theory:: Perturbational long-range electron-interaction corrections -: art. no. 012510 [J].
Angyán, JG ;
Gerber, IC ;
Savin, A ;
Toulouse, J .
PHYSICAL REVIEW A, 2005, 72 (01)
[3]  
Ayala PY, 2000, J COMPUT CHEM, V21, P1524, DOI 10.1002/1096-987X(200012)21:16<1524::AID-JCC9>3.0.CO
[4]  
2-#
[5]   DENSITY-FUNCTIONAL THERMOCHEMISTRY .3. THE ROLE OF EXACT EXCHANGE [J].
BECKE, AD .
JOURNAL OF CHEMICAL PHYSICS, 1993, 98 (07) :5648-5652
[6]   CALCULATION OF SMALL MOLECULAR INTERACTIONS BY DIFFERENCES OF SEPARATE TOTAL ENERGIES - SOME PROCEDURES WITH REDUCED ERRORS [J].
BOYS, SF ;
BERNARDI, F .
MOLECULAR PHYSICS, 1970, 19 (04) :553-&
[7]   Geometry optimization of periodic systems using internal coordinates -: art. no. 124508 [J].
Bucko, T ;
Hafner, J ;
Angyán, JG .
JOURNAL OF CHEMICAL PHYSICS, 2005, 122 (12)
[8]   An ab initio study of solid nitromethane, HMX, RDX, and CL20: Successes and failures of DFT [J].
Byrd, EFC ;
Scuseria, GE ;
Chabalowski, CF .
JOURNAL OF PHYSICAL CHEMISTRY B, 2004, 108 (35) :13100-13106
[9]   Density functional study of hydrogen-bonded systems: Energetic and vibrational features of some gas-phase adducts of hydrogen fluoride [J].
Civalleri, B ;
Garrone, E ;
Ugliengo, P .
JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM, 1997, 419 :227-238
[10]   Critical examination of the supermolecule density functional theory calculations of intermolecular interactions [J].
Cybulski, SM ;
Seversen, CE .
JOURNAL OF CHEMICAL PHYSICS, 2005, 122 (01)