4 resultados para Otthera, Johann von, b. 1479 or 80,

em Brock University, Canada


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A game from the 79/80 or 80/81 season.

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A detailed theoretical investigation of the large amplitude motions in the S, excited electronic state of formic acid (HCOOH) was done. This study focussed on the the S, «- So electronic band system of formic acid (HCOOH). The torsion and wagging large amplitude motions of the S, were considered in detail. The potential surfaces were simulated using RHF/UHF ab-initio calculations for the two electronic states. The energy levels were evaluated by the variational method using free rotor basis functions for the torsional coordinates and harmonic oscillator basis functions for the wagging coordinates. The simulated spectrum was compared to the slit-jet-cooled fluorescence excitation spectrum allowing for the assignment of several vibronic bands. A rotational analysis of certain bands predicted that the individual bands are a mixture of rotational a, b and c-type components.The electronically allowed transition results in the c-type or Franck-Condon band and the electronically forbidden, but vibronically allowed transition creates the a/b-type or Herzberg-Teller components. The inversion splitting between these two band types differs for each band. The analysis was able to predict the ratio of the a, b and c-type components of each band.

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Exchange reactions between molecular complexes and excess acid or base are well known and have been extensively surveyed in the literature(l). Since the exchange mechanism will, in some way involve the breaking of the labile donor-acceptor bond, it follows that a discussion of the factors relating to bonding in molecular complexes will be relevant. In general, a strong Lewis base and a strong Lewis acid form a stable adduct provided that certain stereochemical requirements are met. A strong Lewis base has the following characteristics (1),(2) (i) high electron density at the donor site. (ii) a non-bonded electron pair which has a low ionization potential (iii) electron donating substituents at the donor atom site. (iv) facile approach of the site of the Lewis base to the acceptor site as dictated by the steric hindrance of the substituents. Examples of typical Lewis bases are ethers, nitriles, ketones, alcohols, amines and phosphines. For a strong Lewis acid, the following properties are important:( i) low electron density at the acceptor site. (ii) electron withdrawing substituents. (iii) substituents which do not interfere with the close approach of the Lewis base. (iv) availability of a vacant orbital capable of accepting the lone electron pair of the donor atom. Examples of Lewis acids are the group III and IV halides such (M=B, AI, Ga, In) and MX4 - (M=Si, Ge, Sn, Pb). The relative bond strengths of molecular complexes have been investigated by:- (i) (ii) (iii) (iv) (v] (vi) dipole moment measurements (3). shifts of the carbonyl peaks in the IIIR. (4) ,(5), (6) .. NMR chemical shift data (4),(7),(8),(9). D.V. and visible spectrophotometric shifts (10),(11). equilibrium constant data (12), (13). heats of dissociation and heats of reactions (l~), (16), (17), (18), (19). Many experiments have bben carried out on boron trihalides in order to determine their relative acid strengths. Using pyridine, nitrobenzene, acetonitrile and trimethylamine as reference Lewis bases, it was found that the acid strength varied in order:RBx3 > BC1 3 >BF 3 • For the acetonitrile-boron trihalide and trimethylamine boron trihalide complexes in nitrobenzene, an-NMR study (7) showed that the shift to lower field was. greatest for the BB~3 adduct ~n~ smallest for the BF 3 which is in agreement with the acid strengths. If electronegativities of the substituents were the only important effect, and since c~ Br ,one would expect the electron density at the boron nucleus to vary as BF3<BC1~ BBr 3 and therefore, the acid strength would vary as BF~BC1)BBr3: However, for the boron trihalides, the trend is in the opposite direction as determined experimentally. Considerable back-bonding (20), (21) between the halogen and the boron atoms has been proposed as the predominating factor, i.e. ~rt- back-bond between a lone electron pair on the halogen and the vacant orbital on the boron site. The degree of back-bonding varies inversely as the bo~on halogen distance and one would therefore expect the B-F bond to exhibit greater back-bonding character than the B-Cl or B-Br bonds. Since back-bonding transfers electron density from substituent to the boron atom site, this process would be expected to weaken the Lewis acid strength. This explains the Lewis acid strength increasing in the order BF 3 BC1 3 BBr 3 . When the acetonitrile boron trihalide complex is formed, the boron atom undergoes ~_cbange of hybridization from sp2 to sp3. From a linear relationship between the heat of formation of ethyl acetate adducts and the shift in the carbonyl I.R. stretch, Drago (22) et al have proposed that the angular di~tortion of the X-B-X bonds from sp2 (12 ) to sp3 (10 hybridization is proportional to the amount of charge transferred, i.e. to the nature of the base, and they have rejected the earlier concept of reorganization energy in explaining the formation of the adduct bond (19).

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- The first part of the document traces Mr. Haile’s lineage. His father, James Haile was a farmer. His grandfather, Amos Haile was a sailor for the early part of his life. He was placed on a British man-of- war in about 1758. He escaped and settled in Putney. (p.1) - His father’s mother’s maiden name was Parker. His mother’s maiden name was Campbell. Her father was a captain in the Revolutionary Army. (p.2) - His earliest memories revolve around the death of his aunt and the funeral of General Washington (although he did not witness this). At the time, his father was a Lieutenant in a regiment militia of Light Dragoons who wore red coats. (p.3) - In 1804, an addition was added to the Haile house which necessitated that William was to stay home to help with the building. He continued to study and read on his own. He was particularly interested in Napoleon Bonaparte’s victories. In that same year he was sent to Fairfield Academy where Reverend Caleb Alexander was the principal. (p.4) - On June 1, 1812, William was appointed as an Ensign in the Infantry of the Army of the United States. He was put into the recruiting service at Nassau (20 miles east of Albany) where he remained until September. (p.4) - He was assigned to the 11th Regiment of the W.S. Infantry and directed to proceed to Plattsburgh to report to Colonel Isaac Clark. (p.7) - He was assigned to the company commanded by Captain Samuel H. Halley who was not in the best of health and often absent. For a good part of the time William was in charge of the company. (p.8) - The 11th Regiment was encamped beside the 15th Regiment commanded by Col. Zebulon Montgomery Pike [Pike’s Peak was named after him]. Col. Pike generously drilled and disciplined the 11th Regiment since their officers didn’t seem capable of doing so. (p.8) - The first brigade to which William’s regiment was attached to was commanded by Brigadier General Bloomfield of New Jersey. Brigadier Chandler of Maine commanded the second brigade. (p.9) - At the beginning of November, Major General Dearborn took command of the army. He had been a good officer in his time, but William refers to him as “old and inefficient” earning him the nickname “Granny Dearborn” (p.9) - On November 17th, 1812, General Dearborn moved north with his army. The troops ended up in Champlain. There was no fighting, only a skirmish between a party of men under Colonel Pike and a few British troops who he succeeded in capturing. (p.10) - The troops were moved to barracks for the winter. Colonel Pike’s troops were put into suitable barracks and kept healthy but another part of the army (including the 11th Regiment) were sent to a barracks of green lumber north of Burlington. Disease soon broke out in the damp barracks and the hundreds of deaths soon followed. One morning, William counted 22 bodies who had died the previous night. He puts a lot of this down to an inexperienced commanding officer, General Chandler. (p.11) - At the beginning of 1813, William was stationed as a recruiter on the shore of Shoreham across from Fort Ticonderoga. In February, he returned to Burlington with his recruits. In March he received an order from General Chandler to proceed to Whitehall and take charge of the stores and provisions. In April and May it was decided that his half of the regiment (the First Battalion) should march to Sackett’s Harbour, Lake Ontario. They arrived at Sackett’s Harbour about the 10th of June, a few days after the Battle of Sackett’s Harbour. (p.12) - He was camped near the site of Fort Oswego and got word to head back to Sackett’s Harbour. A storm overtook the schooner that he was on. (p.14) - William was involved in the Battle of Williamsburg (or Chrysler’s Farm) which he calls a “stupid and bungling affair on the part of our generals”.(p. 18) - General Covington was wounded and died a few days after the battle. (p.19) - William speaks of being ill. The troops were ordered to march to Buffalo, but he is able to go to his father’s house in Fairfield where his mother nursed him back to health (p.23) - Upon arrival at Buffalo, the “old fogy Generals” were replaced with younger, more efficient men. (p.25) - On page 27 he sums up a few facts: In 1812, the army was assembled on Lake Champlain with the intention of capturing Montreal, and then Quebec. That year, under General Dearborn the army marched as far as Champlain, then turned back and went into winter quarters. In 1813, the army was assembled at Sackett’s Harbour and that year the campaign ended at French Mills which was 70 or 80 miles from Montreal. In 1814, the army at Buffalo were some 400 miles from Montreal with still the same object in view. - He says that these facts make “a riddle – difficult to explain”. (p.27) - On the evening of July 2nd they embarked on the boats with the objective of capturing Fort Erie. The enemy were all made prisoners of war (p.27) - On July 4th they went to Street’s Creek, 2 miles above the Chippewa [Chippawa] River (p.28) - Page 29 is titled The Battle of Chippewa [Chippawa] - He speaks of 2 drummers who were fighting over the possession of a drum when a cannonball came along and took of both of their heads (p.29) - He proclaims that this was one of the “most brilliant battles of the war”. The battle was fought and won in less than an hour after they left their tents. He credits General Scott with this success and states that was due to his rapid orders and movements. (p.30) - The dead of the battle remained on the field during the night. He describes this as quite gloomy seeing friend and foe lying side by side. At daybreak they set to work digging trenches to bury the dead. (p.31) - Colonel Campbell was wounded and advised to have his leg amputated. He refused, and subsequently died. (p.32) - It is said that the British threw several of their dead into the river and they went over the Falls. (p.32) - His troops repaired the bridge over Chippawa which the enemy had partially destroyed and then pursued the British as far as Queenston Heights. (p.32) - On pages 33 and 34 he speaks about meeting an old friend of his, Philip Harter. - The account ends at Queenston Heights