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Reaction of CdCl., with NC (CIL) n CN, n -1, 3, 4 and 5 produced new complexes. The C = N frequency red and blue shifts were noticed in them. These are explained in terms of interaction between the 5pAO of Cd 2+ and the MOs of the C=N group.It is well known that the vibration frequency of a nitrilo group changes on its coordination to a metal 1 and increases on its hydrogen bridge formation with a proton donating species 2 . Both frequency shifts were attributed to two different kinds of coordination; (a) coordination to the N-lone pair orbital causing an increase in the vibration frequency; (b) ^-coordination to the C = N bond causing a decrease in the vibration frequency 3 . Recent measurements of the vibration frequencies of the C = N groups in alkyl dinitrile complexes showed the two types of shifts. It was noticed that if the ligand acts as a bridge between two metal ions and coordinates through the lone pair orbitals on the nitrogen atoms in the complex Ag 1+ , n = 1, 2) 5 -6 and (M (NC (CH2) ,,CN) CL4 , (M = Ti 4+ , Sn 4+ , n = 1-4) ; 6~8 an increase in the C = N frequency is observed. On the other hand in the complexes M (CO) 3 (NC (CH2) ,,CN) X where the dinitrile coordinates via the triple bond as a bidentate ligand, a decrease in the C = N frequency is observed, (M = Mn 1+ , Re 1+ ; n = 1 -3; X = Cl, Br) 9 ' 10 . We report here an extension of this study to the dinitrilo complexes of Cd 2+ and a theoretical explanation for the observed frequency shifts. Experimental PartThe infrared spectra were measured on a PerkinElmer model 137E infracord spectrophotometer using nujol mulls, and on a Perkin-Elmer spectrophotometer model 257 with a 2.5 fold wave number expansion. The C, H, N analyses were performed by the Alfred Bernhardt Microanalytisches Laboratorium-Mühlheim, West-Germany. Preparation of Bismalononitrile cadmium (II) chloride, hexahydrateTwenty mmoles of malononitrile dissolved in the least amount of isobutanol were added to 10 mmoles of cadmiumchloride dissolved in the least amount of isobutanol also. The mixture was refluxed for 10 hours during which its colour changed from colorless to yellow. After cooling, the formed yellow precipitate was filtered, washed with ethanol and ether and dried under vacuum. Anal, for Cd [ (NC -CH.> -CN).,] CU • 6 H.,0 Calc. C, 17.0 H, 3,7" N, 13,2 Found. C, 16.7 H, 1.25 N, 12.27 Preparation of Chlor ocadmium (II)-fi-glutaronitrile, chlor ocadmium (11) chlorideSixty mmoles of glutaronitrile dissolved in the least amount of isobutanol were added to 30 mmoles of cadmiumchloride dissolved in ethanol and then refluxed for 25 hours. The solvent was then evaporated under vacuum. The formed white precipitate was filtered, washed with ethanol and ether and dried over calciumchloride under vacuum. Preparation of Chlor ocadmium (II)-/n-adiponitrile, chlor ocadmium (II) chlorideFourty mmoles of adiponitrile dissolved in the least amount of isobutanol were added to a solution of 10 mmoles of eadmiumchlorid in a minimum amount of ethanol. The mixture was then refluxed for 24 ...

Politeness strategies are of significant importance to maintain the face of the addressee. Senders of formal congratulatory letters seek to create a positive image in the minds of their addresses by performing particular illocutionary acts and face-saving acts (FSAs) in the form of written texts. To the best knowledge of the researcher, this topic received little attention from linguistic researchers, especially on the pragma-stylistic level. The importance of this study arises from the fact that congratulatory formal letters are an effective tool in the successful performance of foreign relations and thus deserve investigation. The current study investigates the pragma-stylistic aspects of illocutionary acts and FSA Politeness Strategies in some selected English and Arabic formal congratulatory letters written by English and Arabic officials. Findings reveal that assertive constitutes the highest frequency in English data, while expressive occurs more in Arabic. Besides, the FSA politeness strategy (Use appropriate forms of address) includes most of the total frequency in both English and Arabic data, which still it appeared more in English. Additionally, (Exaggerate interest, sympathy with H) comes next in Arabic, while (Be optimistic) appeared more in English. In addition, results show that exaggeration (Hyperbole) is the prevalent stylistic device used in Arabic. Arabic officials usually exaggerate the glorification of people in authoritative positions, while English high officials tend to be more moderate. The findings will be helpful in cross-cultural comparative studies and other related fields.

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