{"product_id":"nickela-electrons-diffract-1927-physics-t-shirt","title":"Nickela – Electrons Diffract 1927 Physics T-Shirt","description":"\u003cp\u003eNickela raises her nickel-crystal shield, and a spray of electrons bounces off as a single bright beam at 50 degrees.\u003c\/p\u003e\u003ch3\u003eThe Physics\u003c\/h3\u003e\u003cp\u003eAt Bell Labs in 1927, Clinton Davisson and Lester Germer fired slow electrons at a single crystal of nickel and measured how many bounced off at each angle. At 54 eV they found a sharp peak at about 50°: a diffraction peak.\u003c\/p\u003e\u003cp\u003eTreating the surface rows of atoms, spaced 0.215 nm apart, as a grating gives a wavelength of 0.165 nm. De Broglie's formula at 54 eV gives 0.167 nm. Electrons behave as waves.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003ed sin φ = λ   and   λ = h \/ √(2m_eE)\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003ed: spacing of surface atom rows (0.215 nm)\u003c\/li\u003e\n\u003cli\u003eφ: scattering angle of the peak (about 50°)\u003c\/li\u003e\n\u003cli\u003eλ: electron wavelength (m)\u003c\/li\u003e\n\u003cli\u003eh: Planck constant (J s)\u003c\/li\u003e\n\u003cli\u003em_e: electron mass (kg)\u003c\/li\u003e\n\u003cli\u003eE: electron kinetic energy (54 eV)\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eDavisson \u0026amp; Germer, “Diffraction of electrons by a crystal of nickel”, Physical Review 30, 705 (1927).\u003c\/p\u003e\u003cp\u003e\u003cem\u003eHonest caveat:\u003c\/em\u003e It was not the only proof: G. P. Thomson independently saw electron diffraction in 1927.\u003c\/p\u003e\u003ch3\u003eOn the shirt\u003c\/h3\u003e\u003cp\u003eFront: Nickela, the pixel-art character, with “ELECTRONS DIFFRACT”. Back: the 54 eV peak at 50°, the grating and de Broglie wavelengths, and the 1927 Physical Review paper. Printed on a unisex tee.\u003c\/p\u003e","brand":"Printify","offers":[{"title":"S \/ White","offer_id":50960523657319,"sku":"30767241001585025373","price":29.99,"currency_code":"USD","in_stock":true},{"title":"S \/ Black","offer_id":50960523690087,"sku":"24097737292650115432","price":29.99,"currency_code":"USD","in_stock":true},{"title":"M \/ White","offer_id":50960523722855,"sku":"27379941320187073170","price":29.99,"currency_code":"USD","in_stock":true},{"title":"M \/ Black","offer_id":50960523755623,"sku":"53576099467294131931","price":29.99,"currency_code":"USD","in_stock":true},{"title":"L \/ White","offer_id":50960523788391,"sku":"18781658806631759515","price":29.99,"currency_code":"USD","in_stock":true},{"title":"L \/ Black","offer_id":50960523821159,"sku":"31567095570744651416","price":29.99,"currency_code":"USD","in_stock":true},{"title":"XL \/ White","offer_id":50960523853927,"sku":"17295286590858412973","price":29.99,"currency_code":"USD","in_stock":true},{"title":"XL \/ Black","offer_id":50960523886695,"sku":"98266450199803787043","price":29.99,"currency_code":"USD","in_stock":true},{"title":"2XL \/ White","offer_id":50960523919463,"sku":"33966556407310694199","price":29.99,"currency_code":"USD","in_stock":true},{"title":"2XL \/ Black","offer_id":50960523952231,"sku":"17094797624658947641","price":29.99,"currency_code":"USD","in_stock":true},{"title":"3XL \/ White","offer_id":50960523984999,"sku":"25954284904820629952","price":29.99,"currency_code":"USD","in_stock":true},{"title":"3XL \/ Black","offer_id":50960524017767,"sku":"30039517182321653670","price":29.99,"currency_code":"USD","in_stock":true},{"title":"4XL \/ White","offer_id":50960524050535,"sku":"32434595674282798210","price":29.99,"currency_code":"USD","in_stock":true},{"title":"4XL \/ Black","offer_id":50960524083303,"sku":"33238016311119954382","price":29.99,"currency_code":"USD","in_stock":true},{"title":"5XL \/ White","offer_id":50960524116071,"sku":"21589092117914461999","price":29.99,"currency_code":"USD","in_stock":true},{"title":"5XL \/ Black","offer_id":50960524148839,"sku":"25686771645134900480","price":29.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0596\/8746\/9159\/files\/davisson-germer-1927_front_16_white.png?v=1793625904","url":"https:\/\/pixelatedphysics.com\/hi\/products\/nickela-electrons-diffract-1927-physics-t-shirt","provider":"Pixelated Physics","version":"1.0","type":"link"}