𝔖 Bobbio Scriptorium
✦   LIBER   ✦

An ab initio study of the structure, dissociation energy, and heat of formation of Na2S

✍ Scribed by Yongfang Zhao; Tingkun Gu; Soufu Pan; Jing Sun

Publisher
John Wiley and Sons
Year
1997
Tongue
English
Weight
148 KB
Volume
61
Category
Article
ISSN
0020-7608

No coin nor oath required. For personal study only.

✦ Synopsis

The equilibrium geometries and fundamental frequencies of Na S are calculated at HF, 2 Ž . Ž . Ž . MP2 FC, FU , and MP3 with the 6-31G d basis set and at HF and MP2 FC, FU with the Ž . Ž . Ž . 6-31G d basis set, respectively. The total energy at MP2 FU r6-31G d -optimized Ž . Ž . Ž . geometry is computed at MP4 with 6-311G d, p , 6-311qG d, p , and 6-311G 2 df, p , at Ž . Ž . Ž . QCISD T r6-311G d, p , and at MP2r6-311G 3df, 2 p levels, respectively. The dissociation energy, the atomization energy, and the heat of formation for Na S are 2 evaluated using the G1 and G2 models. The calculated results indicated that Na S in its 2 Ž . ground state was a bent structure C . Electron correlation corrections on the bending 2 v Ž . angle are very significant. The equilibrium geometrical parameters are R Na᎐S s 2.45 e ˚Ž . Ž . A and ЄNa᎐S᎐Na s 111.13Њ at the MP2 FU r6-31G d level. The theoretically estimated dissociation energy, total atomization energy, and heat of formation are 67.07, 117.55, and 0.35 kcal mol y1 , respectively, at 298.15 K. ᮊ 1997 John Wiley & Sons, Inc. w x Na 3 . Such a suggestion requires both theoretical ( )

📜 SIMILAR VOLUMES

Formation of a2+ ions of protonated pept
Formation of a2+ ions of protonated peptides. An ab initio study
✍ Béla Paizs; Zoltán Szlávik; György Lendvay; Károly Vékey; Sándor Suhai 📂 Article 📅 2000 🏛 John Wiley and Sons 🌐 English ⚖ 288 KB 👁 1 views

The mechanism of the formation of a2+ ions from b2+ ions occurring during fragmentation of protonated peptides is investigated using quantum chemical methods. The geometries of the stationary structures involved in two possible mechanisms, namely, a two-step mechanism via an open-chain acylium ion a

An ab initio study of the N8C12 heterofu
An ab initio study of the N8C12 heterofullerene
✍ Stefano Evangelisti 📂 Article 📅 1997 🏛 John Wiley and Sons 🌐 English ⚖ 165 KB 👁 2 views

The result of an ab initio investigation on the hypothetical system N C 8 12 is presented. This is a fullerene-like structure with T symmetry. Calculations have been h Ž . Ž . performed at self-consistent field SCF , second-order Møller-Plesset MP2 , and density Ž . Ž . functional theory DFT level,

Formation of b2+ ions from protonated pe
Formation of b2+ ions from protonated peptides: an ab initio study
✍ Béla Paizs; György Lendvay; Károly Vékey; Sándor Suhai 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 189 KB 👁 1 views

Systematic ab initio calculations were performed to reveal the mechanism of formation of stable b 2 ions formed during fragmentation of protonated peptides and proteins. Stable oxazolone-type cyclic b 2 ions are formed from parent ions containing the -C(O)-N-C-C(O)-unit in a two-step process. In the