𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Ab initio periodic study of the conformational behavior of glycine helical homopeptides

✍ Scribed by Anna Maria Ferrari; Bartolomeo Civalleri; Roberto Dovesi

Publisher
John Wiley and Sons
Year
2010
Tongue
English
Weight
189 KB
Volume
31
Category
Article
ISSN
0192-8651

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

Representative helicoidal conformations of polyglycine infinite chains have been investigated by using periodic boundary conditions, the B3LYP hybrid functional, and large basis sets, by means of the CRYSTAL code. The exploitation of the helix roto‐translational symmetry permits to optimize at a relatively low cost the structure of systems whose unit cell contains more than 300 atoms, much larger than the one investigated till now. In the present calculations, the helix symmetry is exploited at three levels. First, for the automatic generation of the structure. Second, for the calculation of the one‐ and two‐electron integrals that enter into the Fock matrix definition. Only the irreducible wedge of the Fock matrix is computed. Finally, for the diagonalization of the Fock matrix, where each irreducible representation is separately treated. The efficiency and accuracy of the computational scheme are documented, by considering cells containing up to 47 glycine residues. Results are compared with previous calculations and available experimental data. The role of hydrogen bonding in stabilizing polyglycine conformers is also addressed. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010

📜 SIMILAR VOLUMES

Ab initio study on the photochemical beh
Ab initio study on the photochemical behavior of styrene
✍ Yoshiaki Amatatsu 📂 Article 📅 2002 🏛 John Wiley and Sons 🌐 English ⚖ 136 KB 👁 1 views

## Abstract __Ab initio__ complete active space self‐consistent field (CASSCF) and the second order multireference Møller‐Plesset calculations have been performed to examine the photochemical behavior of styrene upon the strong S~0~‐S~2~ electronic excitation in the low‐lying excited states. The op

Ab initio study of the conformational eq
Ab initio study of the conformational equilibrium of trimethylene cyclic sulfite
✍ J. Guillermo Contreras; Sandra T. Madariaga 📂 Article 📅 2000 🏛 John Wiley and Sons 🌐 English ⚖ 64 KB 👁 1 views

Ab initio calculations, in the frame of MO theory, were carried out on both most stable (chair) conformers of trimethylene cyclic sulfite. Optimized geometries derived at the HF/6-31G\* level reveal that both conformers possess a rigid chair conformation with the S=O group located either axially (co

Study of the conformers of dichloromethy
Study of the conformers of dichloromethylmethyldifluorosilane by vibrational spectroscopy and ab initio methods
✍ Valdemaras Aleksa; Peter Klaeboe; Anne Horn; Claus. J. Nielsen; Gamil A. Guirgis 📂 Article 📅 1998 🏛 John Wiley and Sons 🌐 English ⚖ 421 KB 👁 2 views

## DichloromethylmethyldiÑuorosilane was synthesized for the Ðrst time. Raman spectra of the (CHCl 2 SiF 2 CH 3 ) liquid were obtained at various temperatures between 298 and 163 K. Spectra of the amorphous solid were recorded at 85 K and spectra of crystalline solids cooled by di †erent technique

Ab initio and density functional study o
Ab initio and density functional study of the conformational space of1C4 ?-L-fucose
✍ Csonka, Gabor I.; �li�s, Krisztina; Csizmadia, Imre G. 📂 Article 📅 1997 🏛 John Wiley and Sons 🌐 English ⚖ 213 KB 👁 2 views

The conformational space of 1 C ␣-L-fucose was searched by the MM2\*-SUMM 4 molecular mechanics conformational search technique. The molecular geometries of the first 17 structures of lowest energy were analyzed at the HFr3᎐21G, Ž . Ž .

An Ab initio study on the conformations
An Ab initio study on the conformations of protonated, neutral, and deprotonated amidine
✍ Theresa Julia Zielinski; Michael R. Peterson; Imre G. Csizmadia; Robert Rein 📂 Article 📅 1982 🏛 John Wiley and Sons 🌐 English ⚖ 422 KB 👁 1 views

Ab initio SCF molecular orbital calculations have been performed to ascertain the conformational preferences of protonated, neutral, and deprotonated amidine [HC(=NH)NHz], using the 3-21G split valence basis set. The states of eight stable species, eight transition states, and four higher-order sadd