Daniel Shannon fonds, 1816-1822

Lt. Daniel Shannon fl. 1777-1822, was the only son of Susan Drake, granddaughter of Rev. Thomas Drake, eldest brother of Sir Francis Drake, and Captain Daniel Shannon of the Royal Navy. He married Elizabeth Garvey, daughter of Alexander Garvey and Catharine Borden of New Jersey. Lt. Shannon was a Regular in the British Army and on February 12, 1777 he joined the Royal Standard, 5th New Jersey Volunteers. After being arrested and sentenced to hang for spying he was pardoned through the efforts of his mother Susan Drake Shannon who pleaded his case with the Governor. He served under General Cornwallis at the surrender in Virginia in 1781. In 1783 he moved to New Brunswick, Canada where he was reduced to a half-pay ensign in the 2nd Regiment of the Lincoln Militia. He was granted 500 acres of land on the St. Johns River, and on April 1, 1786 his daughter Catharine was born there. The family returned to the United States, residing in Pennsylvania, for a short time. In 1800 Lt. Shannon, with his mother and family, returned to Canada and settled in Stamford Township where he bought 200 acres of land on the Niagara River near the whirlpool. He later served in the Secret Service during the War of 1812 and was stationed at a lookout point on the Niagara River below the falls. In 1806 Shannon’s daughter, Catharine, married Thomas Lundy, fourth son of William Lundy of Stamford Township.

Application of Reptation Quantum Monte Carlo and Related Methods to LiH

This work investigates mathematical details and computational aspects of Metropolis-Hastings reptation quantum Monte Carlo and its variants, in addition to the Bounce method and its variants. The issues that concern us include the sensitivity of these algorithms' target densities to the position of the trial electron density along the reptile, time-reversal symmetry of the propagators, and the length of the reptile. We calculate the ground-state energy and one-electron properties of LiH at its equilibrium geometry for all these algorithms. The importance sampling is performed with a single-determinant large Slater-type orbitals (STO) basis set. The computer codes were written to exploit the efficiencies engineered into modern, high-performance computing software. Using the Bounce method in the calculation of non-energy-related properties, those represented by operators that do not commute with the Hamiltonian, is a novel work. We found that the unmodified Bounce gives good ground state energy and very good one-electron properties. We attribute this to its favourable time-reversal symmetry in its target density's Green's functions. Breaking this symmetry gives poorer results. Use of a short reptile in the Bounce method does not alter the quality of the results. This suggests that in future applications one can use a shorter reptile to cut down the computational time dramatically.