Hydrogen-bonding term

Rognan published the scoring function FRESNO (fast free energy scoring function), which considers a hydrogen-bond term, a lipophilic terra, a repulsive term for the buried polar surface, a rotational term, and a desolvation terra [82]. 

Some force fields replace the Lennard-Jones 6-12 term between hydrogen-bonding atoms by ail explicit hydrogen-bonding term, which is often described using a 10-12 Lennard-Jones potential ... 

The parameters A and B are those from the force held being used. A few studies have incorporated a hydrogen-bonding term also. 

The OPLS atom types are a superset of the AMBER united atom types and the bonding parameters are just those of AMBER, supplemented where needed by the OPLS developers. The bond stretch, angle bending, dihedral angle and improper dihedral angle terms are identical to those of AMBER. Unlike AMBER, different combination rules are used for the van der Waals parameters, no hydrogen bonding term is used and no lone pairs are used. 

The BIOh- force field option in HyperChem has no hydrogen bonding term. This is consistent with evolution and common use of the CHARMM force field (even the 1983 paper did not use a hydrogen bonding term in its example calculations and mentioned that the functional form used then was unsatisfactory and under review). 

Prop = cavity term + dipolar term + hydrogen-bonding terms... 

As can be seen, all the compounds have a strong solubility interaction. Nonetheless Figure 6 shows that they are also well separated, so the more subtle difference between the other four interaction terms are important for their discrimination, ft is worth noting that pentane interacts only via solubility, benzene has a very small hydrogen bonding term, while hydrogen bonding is present in methanol and acetic acid. 

In PLPscore, both the steric and hydrogen bonding terms are calculated from a piecewise linear potential function (see Fig. 1), instead of a smooth 6-12 Lennard-Jones potential energy function. The difference between the two terms is simply in the parameter values chosen for each term. 

LSER Model of Leahy In the LSER model of Leahy [22], the cavity term is substituted by the molar volume, Vm, at 25°C in g cm-3 or by the intrinsic molecular volume, V), in mLmoL1. The dipolar term and the hydrogen-bonding terms are represented by the dipole moment, n, and the HBA basicity, (3, respectively. Group contribution schemes have been developed to calculate the solvatochromic parameters from molecular structure input [23]. Leahy [22] gives the following equation derived with a diverse set of monofunctional liquids ... 

The nucleation mechanism of dispersion polymerization of low molecular weight monomers in the presence of classical stabilizers was investigated in detail by several groups [2,6,7]. It was, for example, reported that the particle size increased with increasing amount of water in the continuous phase (water/eth-anol), the final latex radius in their dispersion system being inversely proportional to the solubility parameter of the medium [8]. In contrast, Paine et al.[7] reported that the final particle diameter showed a maximum when Hansen polarity and the hydrogen-bonding term in the solubility parameter were close to those of steric stabilizer. 

The explanation for Chargaff s rules is provided by die selective hydrogen bonds, termed complementary base pairing, that form between adenine and thymine molecules and between guanine and cytosine. Adenine and thymine form two hydrogen bonds with an overall strength of about 10 kcal/mol (42 kJ/mol) ... 

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