Phonon spectra and temperature variation of thermodynamic properties of fcc metals via Finnis-Sinclair type many body potentials: Sutton-Chen and improved Sutton-Chen models

Volume(density)-independent pair-potentials cannot describe metallic cohesion adequately as the presence of the free electron gas renders the total energy strongly dependent on the electron density. The embedded atom method (EAM) addresses this issue by replacing part of the total energy with an explicitly density-dependent term called the embedding function. Finnis and Sinclair proposed a model where the embedding function is taken to be proportional to the square root of the electron density. Models of this type are known as Finnis-Sinclair many body potentials. In this work we study a particular parametrization of the Finnis-Sinclair type potential, called the "Sutton-Chen" model, and a later version, called the "Quantum Sutton-Chen" model, to study the phonon spectra and the temperature variation thermodynamic properties of fcc metals. Both models give poor results for thermal expansion, which can be traced to rapid softening of transverse phonon frequencies with increasing lattice parameter. We identify the power law decay of the electron density with distance assumed by the model as the main cause of this behaviour and show that an exponentially decaying form of charge density improves the results significantly. Results for Sutton-Chen and our improved version of Sutton-Chen models are compared for four fcc metals: Cu, Ag, Au and Pt. The calculated properties are the phonon spectra, thermal expansion coefficient, isobaric heat capacity, adiabatic and isothermal bulk moduli, atomic root-mean-square displacement and Gr\"{u}neisen parameter. For the sake of comparison we have also considered two other models where the distance-dependence of the charge density is an exponential multiplied by polynomials. None of these models exhibits the instability against thermal expansion (premature melting) as shown by the Sutton-Chen model. We also present results obtained via pure pair potential models, in order to identify advantages and disadvantages of methods used to obtain the parameters of these potentials.

Fairview School class photograph, ca. 1930

Individuals in the photograph are identified as follows: Front Row, L to R: Stuart McDonald, Pete Burtch, Carl Schwenker, Bill Davey, Jim Barnes, ? McDonald, Marie Youngblutt, Lorraine Havens, Margaret Sinclair, Carla Prince, Verna Sinclair, Helen Welsh, Margaret Welsh, Elsie Backshall, Smith girl, Amy McDonald. 2nd Row, L to R: Nelson Sinclair, Gordon Wilson, Ivan Burtch, ? Smith, George Corman, Roy Burtch, Mort Corman, Bob Bell, ?Wilson, Jim Combe, Murray Combe, Jack High, George Welsh, Larry Downes, Gordon Schwenker, Albert Davey, Harvey Davey. Back Row, L to R: Bert Sinclair, Jim Mason, Len Corman, Johnny Corman, David Hallett, Lloyd Graham, Paul Harndon?, Gordon Dormes, George Bell, Doug Garriock, ?McDonald, Mary? Honsberger, Mary Backus, Hilda Wilson. The teacher may be Beatrice Armstrong. Fairview School was built in 1919 in Louth Township, Lincoln County, Ont. It may have been built around the time the county constructed other schools, namely, Grapeview and Glenridge. Nicholson and Macbeth may have been the architects of this school, as some features on the building, ie. the carved stone children’s faces below the lintel of the front door , appear in another known and proven Nicholson and Macbeth building, the former YMCA on Queen Street in St. Catharines. The school remained in operation until 1979 when it was purchased for a church, the Fairview-Louth Community church, which later became Southridge Community church, now located on Glenridge Avenue, St. Catharines, Ont. Today the building is occupied by the Niagara Korean Presbyterian Church.

Personal Seals of Sir Isaac Brock

Two orange coloured seals containing the impression of the personal seal of Sir Isaac Brock. The seal depicts a crest containing a lion in the upper portion and an eagle with its wings spread in the lower portion, which represent strength, clarity of vision and courage. Below the crest is a banner with "Canada" written on it. Above the crest is an Indian on a battlement holding a tomahawk, which represents the alliance Brock had forged with the First Nations. The seals are in a John Sinclair tobacco tin.

Fairview School class photograph, ca. 1930.

Fairview School (9th Street Louth, St. Catharines, Ontario) photograph, ca. 1933 Individuals in the photograph are identified as follows: Front Row, L to R: Stuart McDonald, Pete Burtch, Carl Schwenker, Bill Davey, Jim Barnes, ? McDonald, Marie Youngblutt, Lorraine Havens, Margaret Sinclair, Carla Prince, Verna Sinclair, Helen Welsh, Margaret Welsh, Elsie Backshall, Smith girl, Amy McDonald. 2nd Row, L to R: Nelson Sinclair, Gordon Wilson, Ivan Burtch, ? Smith, George Corman, Roy Burtch, Mort Corman, Bob Bell, ?Wilson, Jim Combe, Murray Combe, Jack High, George Welsh, Larry Downes, Gordon Schwenker, Albert Davey, Harvey Davey. Back Row, L to R: Bert Sinclair, Jim Mason, Len Corman, Johnny Corman, David Hallett, Lloyd Graham, Paul Harndon?, Gordon Dormes, George Bell, Doug Garriock, ?McDonald, Mary? Honsberger, Mary Backus, Hilda Wilson. The teacher may be Beatrice Armstrong.

Woodruff Family fonds, 1784 – 1983, (non-inclusive)

The Woodruff Family Collection: From the time the Woodruff Family came to Canada from the United States in 1795, they took an active role in the forming of their communities both in a civic and social manner. This is evident through the documents contained in this collection. The Woodruffs played an active role in the battles fought in Upper Canada and they were an integral part of the Village of St. Davids. They were educated, business-minded and socially engaged. They accumulated much of their fortune through land dealings. Much of this collection focuses on Samuel DeVeaux Woodruff who was principally a businessman. His dedication to his work is shown through his numerous undertakings. He made his mark on the Niagara Peninsula through his work on the railways, roads, marsh land revisions, canals and the paper industry. He was also involved with the founding of the Long Point Company and he took control of building DeVeaux Hall down to the last detail. His offspring inherited his work ethic and his business acumen. The people who married into the Woodruff Family also possessed key social, political and business ties. Anne and Margaret Clement were from a staunch Loyalist background. Samuel Zimmerman was instrumental to the founding of Niagara Falls and Judge Samuel DeVeaux left behind a legacy for poor and homeless boys in Niagara Falls, New York. The Woodruff Family undoubtedly left a mark on the Niagara Peninsula. This collection brings to light many endeavours of the family and their varied contributions.

Artists Rendering of Isobel Price

Artist’s rendering in colour of Isobel Price in an oval frame with a hook at the top and a section at the back which contains a lock of hair. This painting was done by Gerald Sinclair Hayward who was a renowned artist whose work was displayed at an exhibition in New York in 1899. He painted Theodore Roosevelt, William K. Vanderbilt and members of the ruling families of Britain, Germany and Russia. The frame is enclosed in a folding case lined with velvet and silk. The silk is quite worn. The outside of the case appears to be leather and has a stand for setting it upright. It closes with a metal latch. This is accompanied by a note by R. Band.