Semi-experimental equilibrium structure of pyrazinamide from gas-phase electron diffraction. How much experimental is it?

详细信息    查看全文

• 作者：Denis S. Tikhonov^a ; ^b ; ^{dentix@phys.chem.msu.ru} ; Yury V. Vishnevskiy^a ; Anatolii N. Rykov^b ; Olga E. Grikina^b ; Leonid S. Khaikin^b
• 关键词：Pyrazinamide ; Gas electron diffraction ; Regularization ; Amount of information ; Heuristic criterion ; Quantum chemistry
• 刊名：Journal of Molecular Structure
• 出版年：2017
• 出版时间：15 March 2017
• 年：2017
• 卷：1132
• 期：Complete
• 页码：20-27
• 全文大小：769 K
• 卷排序：1132

文摘

A semi-experimental equilibrium structure of free molecules of pyrazinamide has been determined for the first time using gas electron diffraction method. The refinement was carried using regularization of geometry by calculated quantum chemical parameters. It is discussed to which extent is the final structure experimental. A numerical approach for estimation of the amount of experimental information in the refined parameters is suggested.The following values of selected internuclear distances were determined (values are in Å with 1σ in the parentheses): re(Cpyrazine—Cpyrazine)av = 1.397(2), re(Npyrazine—Cpyrazine)av = 1.332(3), re(Cpyrazine—Camide) = 1.493(1), re(Namide—Camide) = 1.335(2), re(Oamide—Camide) = 1.219(1). The given standard deviations represent pure experimental uncertainties without the influence of regularization.