Dipole moment of chlorobenzene

I) the dipole moment of chlorobenzene Is lower than that of cyclohexyl chloride (ii) alkyl halides, though polar, are Immiscible with water ... 

If there is more than one bond dipole moment in a molecule, then the molecular dipole moment is the vector sum of the individual moments. This idea can be useful in determining the structures and bonding of molecules. For example, Sm5dh determined that the three isomers of dichlorobenzene have dipole moments of 2.30, 1.55, and 0 D. The dipole moment of chlorobenzene was known to be 1.61 D. Smyth reasoned that two C-Cl bond dipole moments add to each other in one isomer of dichlorobenzene, that they cancel each other partially in a second isomer, and that they cancel each other completely in the third isomer. Using the relationship... 

By considering changes of exchange and overlap integrab too. with a little more refined calculation the dipole moment of chlorobenzene was calculated as 0.45 debye. The experimental value b 0.43 debye. 

The dipole moment of chlorobenzene (C6H5CI) is 1.56 D and that of nitrobenzene (C6H5NO2) is 3.97 D. The dipole moment of/iini-chloronitrobenzene is 2.57 D. What does this value indicate about the direction of the moments of the two groups with respect to the benzene ring ... 

The bond polarities of aryl-halogen and aryl-oxygen bonds compared to those in alkyl hahdes and alcohols provide a measure of the effect of the sp hybrid orbital on the O bond and of the resonance interactions between the nonbonded electrons of the substituent and the aromatic ring. The dipole moment of chlorobenzene is smaller than the dipole moment of chlorocyclohexane. 

The dipole moments of chlorobenzene and phenol are 1.7 and 1.5 D, respectively. Predict the dipole moment of -chlorophenol. 

Analysis of bond moment vectors shows that chlorobenzene and pentachlorobenzene are another pair of molecules that would have identical dipole moments if the C—H and C—Cl bond moments were transferable. However, the actual dipole moment of C6HC15 (0.88Z)) is less than that of chlorobenzene (1.70Z>), and the same is true for fluorobenzene (1.53Z)) and pentafluorobenzene (1.38Z))40. Both cases can be explained in terms of the number of halogens competing for the polarizable charge31. 

A dipole moment ii associatod With a permanent uneven sharing of electron density in a molecule. It is a vector quantity that depends on the size of the partial charges in the molecule and the distance between them, and is measured in units of Debye ([if For example, chlorobenzene has a dipole moment of 1 75 D oriented towards the chlorine, in 1,4-dichlorobenzene, the individual moments directed towards the dilorine atoms are equal and opposed to each other, Consequently, the dip ok momenl of this molecuk is zurc. 

However, we see that this is not the case. Chlorobenzene and bromobenzene have dipole moments of only 1.7 d, and vinyl chloride and vinyl bromide have dipole moments of only 1.4 d. This is consistent with the resonance picture of these molecules. In the structures that contain doubly-bonded halogen (III, IV,... 

One liquid for which the value of seems suspect is 1-bromonaphthalene. It contains a polar carbon-bromine bond. I have not been able to find the dipole moment of 1-bromonaphthalene, but the values for bromobenzene, chlorobenzene and fluorobenzene which are chemically similar to 1-bromonaphthalene are 1.70 D, 1.69 D and 1.60 D, respectively. These molecules are almost as polar as chloromethane (1.97 D) and bromomethane (1.81 D), where the polarity of the... 

In a preceeding series of papers [1-8], was investigated the influence of the solvents on the spectral bands of benzene, chlorobenzene, bromobenzene, toluene, anisole, benzaldehyde, nitrobenzene, and benzonitrile with the aim to establish the behaviour differences between monosubstituted benzene molecules with the first and second order susbstituents in solutions, i.e. to contribute to the elucidation of the interactions in the solute-solvent systems determining the spectral displacements, and to evaluate the dipole moments of the solute molecules in their excited states as indices of reactivity. In the series of monosubstituted benzenes the aniline molecule has a place apart due to the presence of the amino group, and it is the object of this investigation. 

Williams (1936) ° observed the infrared absorption of hydrogen chloride in CeHg, C6H5NO2, and m-N02C6H4CH3, labeled as nonionizing solvents. He claimed a correlation between the shift of the 3.45-/H band of HCl and the dipole moment of the solvent. He admitted that there was some difficulty in measuring the HQ absorption in benzene and chlorobenzene owing to the proximity of solvent bands. 

Knowing the electric dipole moment pj of a chlorobenzene (phenyl chloride) molecule (CgHjCl) (pi = 1.59 D), find the dipole moment of ortho-dichlorobenzene (ortho-di-phenyl chloride) pj. 

Because carbon is sp hybridized m chlorobenzene it is more electronegative than the sp hybridized carbon of chlorocyclohexane Consequently the withdrawal of electron density away from carbon by chlorine is less pronounced m aryl halides than m alkyl halides and the molecular dipole moment is smaller... 

It should be possible to test Vorlander s theory of the induction of dipole moments, which e.g. may strengthen the polar character of the C—Cl bond (in 0- and />-chloronitrobenzene) or weaken it (in the m -compound) by comparing the moments of suitable compounds. If the moment of the C—Cl bond is really greater in /)-nitrochlorobenzene than in chlorobenzene, and conversely if... 

The difference between the chemical behaviour of the substitution products of benzene and the corresponding aliphatic derivatives are well known and are reflected in the values of their dipole momcnxs [Table XCVI), In chlorobenzene, in addition to the bond resonance structures, I and //, there are three additional structures ///, IV and V contributing to the molecular resonance and the dipole moment is lowered in comparison with the alkyl halides. 

Studies of the photodissociation dynamics of chlorinated benzene derivatives have been reviewed. Photodissociation of chlorobenzene at 266 nm has been investigated by the crossed laser-molecular beam technique, and a hot molecule mechanism is considered probable. Similar studies have been carried out for bromobenzene and p-bromotoluene, which show that for each of these molecules the dissociation is fast and the transition dipole moment is almost perpendicular to the C-Br bond. In deoxygenated aqueous solutions, 254 nm photolysis of chlorobenzene yields phenol and chloride ions as the main products, along with benzene, phenylphenols and biphenyl.lodo-benzene adsorbed on sapphire(OOOl) at 110 K undergoes C-I bond cleavage when irradiated at 193 nm. ... 

An example is given in reference (9), where a broad absorption in H-bonded alcohols is compared with the band of chlorobenzene. In such extreme situations as those displayed in liquids alcohols, there is little chance of ever extracting successfully the librational features from the total broad absorption patterns. But for simplest liquids such as chlorobenzene, and still more for other compounds possessing higher volumic dipole moments and not involved in complexation nor association, band-shapes are fairly attributable to librational motion. In such favourable cases the analysis of bandshapes puts forward two broadening processes arising from both spatial and temporal fluctuations of local order. 

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