National Technical Reports Library

The National Technical Information Service acquires, indexes, abstracts, and archives the largest collection of U.S. government-sponsored technical reports in existence. The NTRL offers online, free and open access to these authenticated government technical reports. Technical reports and documents in its repository may be available online for free either from the issuing federal agency, the U.S. Government Publishing Office’s Federal Digital System website, or through search engines.

Details

Nitrogen Pentafluoride: Covalent NF5 Versus Ionic NF4(+)F(-) and Studies on the Instability of the Latter. (Reannouncement with New Availability Information).

ADA264201

Publication Date	1992
Personal Author	Christe, K. O.; Wilson, W. W.
Page Count	4
Abstract	Recent ab initio calculations suggesting that covalent NF5 and even NF6(-) are vibrationally stable and might be experimentally accessible prompted us to critically evaluate the presently available theoretical and experimental data for NF5 and to carry out experiments on the stability of ionic NF4F(-). It is shown that covalent NF5 of D(sub 3h) symmetry and crystalline NF4(+)F(-) should be of comparable energy but that covalent NF5 should suffer from severe ligand-crowding effects that would make its synthesis experimentally very difficult. On the other hand, crystalline NF4(+)F(-) should be readily accessible from the well-known solvated NF4(+) and F(-) ions. The recent discoveries of a convenient synthesis of truly anhydrous N(CH3)4F as a source of soluble 'naked' fluoride ions and of solvents which possess sufficient kinetic stability toward strong oxidizers allowed us to carry out experiments on the thermal stability of NF4(+)F(-). It is shown that at temperatures as low as -142 deg C crystalline NF4(+)F(-) is unstable toward decomposition to NF3 and F2, a process which is calculated to be exothermic by about 32 kcal/mol.
Keywords	Fluorides Nitrogen compounds Covalent bonds Molecular ions Decomposition Ions Kinetics Solvents Symmetry Thermal stability Reprints Exothermic reactions Nitrogen fluorides Molecular structure
Source Agency	Army Non Paid Reprints
NTIS Subject Category	99F - Physical & Theoretical Chemistry 99D - Basic & Synthetic Chemistry
Corporate Authors	Rocketdyne, Canoga Park, CA.; Army Research Office, Research Triangle Park, NC.
Document Type	Journal Article
NTIS Issue Number	199607
Contract Number	DAAL03-88-C-0005

Nitrogen Pentafluoride: Covalent NF5 Versus Ionic NF4(+)F(-) and Studies on the Instability of the Latter. (Reannouncement with New Availability Information).

Nitrogen Pentafluoride: Covalent NF5 Versus Ionic NF4(+)F(-) and Studies on the Instability of the Latter. (Reannouncement with New Availability Information).
ADA264201

Publication Date	1992
Personal Author	Christe, K. O.; Wilson, W. W.
Page Count	4
Abstract	Recent ab initio calculations suggesting that covalent NF5 and even NF6(-) are vibrationally stable and might be experimentally accessible prompted us to critically evaluate the presently available theoretical and experimental data for NF5 and to carry out experiments on the stability of ionic NF4F(-). It is shown that covalent NF5 of D(sub 3h) symmetry and crystalline NF4(+)F(-) should be of comparable energy but that covalent NF5 should suffer from severe ligand-crowding effects that would make its synthesis experimentally very difficult. On the other hand, crystalline NF4(+)F(-) should be readily accessible from the well-known solvated NF4(+) and F(-) ions. The recent discoveries of a convenient synthesis of truly anhydrous N(CH3)4F as a source of soluble 'naked' fluoride ions and of solvents which possess sufficient kinetic stability toward strong oxidizers allowed us to carry out experiments on the thermal stability of NF4(+)F(-). It is shown that at temperatures as low as -142 deg C crystalline NF4(+)F(-) is unstable toward decomposition to NF3 and F2, a process which is calculated to be exothermic by about 32 kcal/mol.
Keywords	Fluorides Nitrogen compounds Covalent bonds Molecular ions Decomposition Ions Kinetics Solvents Symmetry Thermal stability Reprints Exothermic reactions Nitrogen fluorides Molecular structure
Source Agency	Army Non Paid Reprints
NTIS Subject Category	99F - Physical & Theoretical Chemistry 99D - Basic & Synthetic Chemistry
Corporate Authors	Rocketdyne, Canoga Park, CA.; Army Research Office, Research Triangle Park, NC.
Document Type	Journal Article
NTIS Issue Number	199607
Contract Number	DAAL03-88-C-0005