MOLECULAR FORCE FIELD FOR SULFUR TETRAFLUORIDE

1965 ◽  
Vol 43 (2) ◽  
pp. 463-469 ◽  
Author(s):  
M. G. Krishna Pillai ◽  
K. Ramaswamy ◽  
R. Pichai
Keyword(s):  
Force Field ◽  
Bond Length ◽  
Force Constant ◽  
Lone Pair ◽  
Bond Pair ◽  
Molecular Force ◽  
Axial Stretching ◽  
Sulfur Tetrafluoride ◽  
The Relationship ◽  
Lone Pair Interactions

An attempt has been made to modify the UBFF for SF4 by taking into account the presence of the lone pair of electrons. It has been found that the bond pair – lone pair interactions become of importance only when the angle between the bond pair and the lone pair approaches 90°. The equatorial S—F stretching force constant (4.0146 mdyn/Å) is greater than the axial stretching force constant (3.6237 mdyn/Å), which is consistent with the form of the relationship between the force constant and bond length.

Molecular force field for chlorine trifluoride

1965 ◽  
Vol 18 (3) ◽  
pp. 261 ◽  
Author(s):  
MG Krishna ◽  
K Ramaswamy ◽  
R Pichai
Keyword(s):  
Force Field ◽  
Force Constant ◽  
Lone Pair ◽  
Pair Interaction ◽  
Pair Bond ◽  
Approximate Relation ◽  
Lone Pairs ◽  
Bond Pair ◽  
Molecular Force ◽  
Molecular Force Field

An attempt has been made to modify the UBFF for chlorine trifluoride by taking into account the presence of lone pairs of electrons, on the lines suggested by Pariseau, Wu, and Overend. It was found that the lone-pair-bond-pair interaction is less than the lone-pair-lone-pair interaction which is considerably lower than the stretching force constant for the lone pair of electrons. An approximate relation between the above interactions was obtained.

Molecular force field for bromine pentafluoride

1968 ◽  
Vol 46 (14) ◽  
pp. 2393-2397 ◽  
Author(s):  
M. G. Krishna Pillai ◽  
P. Parameswaran Pillai
Keyword(s):  
Force Field ◽  
Lone Pair ◽  
Pair Interaction ◽  
Pair Bond ◽  
Halogen Atoms ◽  
Bond Pair ◽  
Molecular Force ◽  
Molecular Force Field ◽  
Lone Pair Electrons

An attempt has been made to study the influence of lone pair electrons on the potential constants of BrF5 with a modified Urey–Bradley force field. It is found that the lone pair – bond pair repulsion is greater than the bond pair – bond pair repulsion. It is also concluded from a study of other molecules containing halogen atoms that the ratio of lone pair – bond pair interaction to bond pair – bond pair interaction is very nearly 1.23.

Molecular Force Field for Seleninyl Fluoride

1970 ◽  
Vol 25 (3) ◽  
pp. 246-249
Author(s):  
M. G. Krishna Pillai ◽  
P. Parameswaran Pillai
Keyword(s):  
Double Bond ◽  
Force Field ◽  
Fixed Ratio ◽  
Lone Pair ◽  
Pair Bond ◽  
Double Bond Character ◽  
Bond Pair ◽  
Molecular Force ◽  
Lone Pair Electrons ◽  
Bond Character

A modified U.B.F.F. containing terms directly related to lone pair electrons, has been used to evaluate the potential constants of SeOF2. The value obtained for the Se-O stretching constant supports the double bond character of the bond. The lone pair-bond pair repulsion bears a fixed ratio to the non-bonded repulsion (FeF/FFF=1.24 and Feo/FoF=1.23) and this result is in agreement with earlier conclusions.

Molecular force field for thionyl fluoride and sulphuryl fluoride

1967 ◽  
Vol 20 (6) ◽  
pp. 1055 ◽  
Author(s):  
R Pichai ◽  
MGK Pillai ◽  
K Ramaswamy
Keyword(s):  
Oxygen Atom ◽  
Potential Energy ◽  
Force Field ◽  
Spectral Data ◽  
Lone Pair ◽  
Molecular Force ◽  
Molecular Force Field ◽  
Energy Constants

The potential energy constants of thionyl fluoride and sulphuryl fluoride were calculated using a modified UBRF. The behaviour of the oxygen atom is found to be similar to that of the lone pair of electrons in thionyl fluoride. The vibrational mean amplitudes of thionyl fluoride and sulphuryl fluoride were also calculated from the vibrational spectral data.

Molecular force field evaluation by empirical constraints

1976 ◽  
Vol 73 ◽  
pp. 1051-1057
Author(s):  
Sadao Isotani ◽  
Alain J.-P. Alix
Keyword(s):  
Force Field ◽  
Field Evaluation ◽  
Molecular Force ◽  
Molecular Force Field

Bond-length distributions for ions bonded to oxygen: Metalloids and post-transition metals

2017 ◽  
Author(s):  
Olivier Charles Gagné ◽  
Frank Christopher Hawthorne
Keyword(s):  
Transition Metal ◽  
Transition Metals ◽  
Metal Ions ◽  
Bond Length ◽  
Lone Pair ◽  
Transition Metal Ions ◽  
Oxygen Lone Pair

Bond-length distributions are examined for thirty-three configurations of the metalloid ions and fifty-six configurations of the post-transition-metal ions bonded to oxygen. Lone-pair stereoactivity is discussed.

Bond-length distributions for ions bonded to oxygen: Metalloids and post-transition metals

2017 ◽  
Author(s):  
Olivier Charles Gagné ◽  
Frank Christopher Hawthorne
Keyword(s):  
Transition Metal ◽  
Transition Metals ◽  
Metal Ions ◽  
Bond Length ◽  
Lone Pair ◽  
Transition Metal Ions ◽  
Oxygen Lone Pair

Bond-length distributions are examined for thirty-three configurations of the metalloid ions and fifty-six configurations of the post-transition-metal ions bonded to oxygen. Lone-pair stereoactivity is discussed.

Bond-length distributions for ions bonded to oxygen: Results for the non-metals and discussion of lone-pair stereoactivity and the polymerization of PO4

2017 ◽  
Author(s):  
Olivier Charles Gagné ◽  
Frank Christopher Hawthorne
Keyword(s):  
Metal Ions ◽  
Bond Length ◽  
Lone Pair ◽  
Group 14 ◽  
Oxygen Lone Pair

Bond-length distributions are examined for three configurations of the H+ ion, sixteen configurations of the group 14-16 non-metal ions and seven configurations of the group 17 ions bonded to oxygen. Lone-pair stereoactivity for ions bonded to O<sup>2-</sup> is discussed, as well as the polymerization of the PO<sub>4</sub> group.

Relations between Varshni and Morse potential energy parameters

Open Physics ◽  
2009 ◽  
Vol 7 (1) ◽  
Author(s):  
Teik-Cheng Lim ◽  
Rajendra Udyavara
Keyword(s):  
Potential Energy ◽  
Force Constant ◽  
Morse Potential ◽  
Morse Function ◽  
Energy Integral ◽  
Equal Energy ◽  
Molecular Force ◽  
Parameter Conversion ◽  
Bond Stretching ◽  
Small Change

AbstractA set of relationships between the Morse and Varshni potential functions for describing covalent bondstretching energy has been developed by imposing equal force constant and equal energy integral. In view of the extensive adoption of Morse function in molecular force fields, this paper suggests two sets of parameter conversions from Varshni to Morse. The parameter conversion based on equal force constant is applicable for small change in bond length, while the parameter conversion based on equal energy integral is more applicable for significant bond-stretching. Plotted results reveal that the Varshni potential function is more suitable for describing hard bonds rather than soft bonds.

Sign in / Sign up

Export Citation Format

Share Document