Uncovering Radiation Chemistry in the Solid State Through Periodic Density-Functional Calculations: Confrontation with Experimental Results and Beyond

2014 ◽  
pp. 667-702 ◽  
Author(s):  
Ewald Pauwels
Keyword(s):  
Solid State ◽  
Density Functional Calculations ◽  
Density Functional ◽  
Radiation Chemistry ◽  
Experimental Results

scholarly journals Iron(II) complexes of dimethyltriazacyclophane

2018 ◽  
Vol 74 (12) ◽  
pp. 1641-1649
Author(s):  
Wei-Tsung Lee ◽  
Matthias Zeller ◽  
David Upp ◽  
Yuliya Politanska ◽  
Doug Steinman ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Solid State ◽  
Dft Calculations ◽  
Density Functional Calculations ◽  
Density Functional ◽  
Coordination Mode ◽  
Functional Theory ◽  
Metal Centers ◽  
Bonding Interaction

Treatment of the ortho-triazacyclophane 1,4-dimethyltribenzo[b,e,h][1,4,7]triazacyclonona-2,5,8-triene [(C6H5)3(NH)(NCH3)2, L1] with Fe[N(SiMe3)2]2 yields the dimeric iron(II) complex bis(μ-1,4-dimethyltribenzo[b,e,h][1,4,7]triazacyclonona-2,5,8-trien-7-ido)bis[(μ-1,4-dimethyltribenzo[b,e,h][1,4,7]triazacyclonona-2,5,8-trien-7-ido)iron(II)], [Fe(C20H18N3)4] or Fe2(L1)4 (9). Dissolution of 9 in tetrahydrofuran (THF) results in solvation by two THF ligands and the formation of a simpler monoiron complex, namely bis(μ-1,4-dimethyltribenzo[b,e,h][1,4,7]triazacyclonona-2,5,8-trien-7-ido-κN 7)bis(tetrahydrofuran-κO)iron(II), [Fe(C20H18N3)2(C4H8O)2] or (L1)2Fe(THF)2 (10). The reaction is reversible and 10 reverts in vacuo to diiron complex 9. In the structures of both 9 and 10, the monoanionic triazacyclophane ligand L1− is observed in only the less-symmetric saddle conformation. No bowl-shaped crown conformers are observed in the solid state, thus preventing chelating κ3-coordination to the metal as had been proposed earlier based on density functional theory (DFT) calculations. Instead, the L1− ligands are bound in either a η2-chelating fashion through the amide and one amine donor (for one of the four ligands of 9), or solely through their amide N atoms in an even simpler monodentate η1-coordination mode. Density functional calculations on dimer 9 revealed nearly full cationic charges on each Fe atom and no bonding interaction between the two metal centers, consistent with the relatively long Fe...Fe distance of 2.912 (1) Å observed in the solid state.

scholarly journals A Density-Functional Study of the Conformational Preference of Acetylcholine in the Neutral Hydrolysis

Molecules ◽  
2020 ◽  
Vol 25 (3) ◽  
pp. 670 ◽  
Author(s):  
Rizka N. Fadilla ◽  
Febdian Rusydi ◽  
Nufida D. Aisyah ◽  
Vera Khoirunisa ◽  
Hermawan K. Dipojono ◽  
...  
Keyword(s):  
Transition State ◽  
Density Functional Calculations ◽  
Density Functional ◽  
Experimental Results ◽  
Functional Study ◽  
Conformational Preference ◽  
Reaction Energy ◽  
Density Functional Study ◽  
One Step ◽  
Experimental Findings

Acetylcholine, which is associated with Alzheimer’s disease, is widely known to have conformers. The preference of each conformer to undergo neutral hydrolysis is yet to be considered. In this study, we employed density-functional calculations to build the conformers and investigated their preference in one-step neutral hydrolysis. The results showed the preference in ten possible hydrolysis pathways involving seven acetylcholine conformers (reactant), four transition state structures, and two choline conformers (product). Three out of the seven acetylcholine conformers predicted from the results confirmed experimental findings on the conformers stability. We suggested that two out of ten possible pathways were observed in the experimental results based on agreement in reaction energy. Eventually, this study will emphasize the importance of considering acetylcholine conformers in its hydrolysis study.

Solid State Density Functional Calculations for the Group 11 Monohalides.

ChemInform ◽  
2005 ◽  
Vol 36 (13) ◽  
Author(s):  
Tilo Soehnel ◽  
Holger Hermann ◽  
Peter Schwerdtfeger
Keyword(s):  
Solid State ◽  
Density Functional Calculations ◽  
Density Functional ◽  
State Density

Solid State Density Functional Calculations for the Group 11 Monohalides

2005 ◽  
Vol 109 (1) ◽  
pp. 526-531 ◽  
Author(s):  
Tilo Söhnel ◽  
Holger Hermann ◽  
Peter Schwerdtfeger
Keyword(s):  
Solid State ◽  
Density Functional Calculations ◽  
Density Functional ◽  
State Density
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