 नेक्छ लीहे क्ब रहांगㅠ territory. We will have the atoms at corner always. Corner plus body center. Ok? Now, in this what happens actually if you compare the simple cubic unit cell, where atoms only corner present. So, you can imagine here at 1 atom here and here. Here you see this space is void, there is a void in the center. Can you imagine this, simple cubic unit cell imagine where the atoms only at the corners, ठें युट बॉईट अरीद अ्ने रनिः, ओगा दिकना महाँ भाईट अगे मलच णो रहीं करते हैका यो लगा रनिएं अरीट अरीट यै अरीट टे सेंट करेट यहाँ दिख़ट मूर देची से इसकों इहीं तो सहने आटम कुई अ आपा भी देची देची अ अपा दिस कोगे अद्ब रहाँ पादा, गे देका हौगे, देची से अद्ब चका इसकोचगे. तो यहाप ये खी पलेश खिल आटम, तो बराब पर परचिजातग क्रोनर आटमट्टेख देखतें, औन येवेस क्या भबा दीस तो खोरे आटम देखतें है. तो तो गब पपप्प याश्टब तो वर च्एन सोगी च्छाँँए, आट में अदज़़ाा क्र्डिएगिया है। अर्वाखन, बाडिज़़, यिखिव। नहीर अर्वाव। ऎदवं थे ज़ी। जी तम योंगे अदवाखना़ तुवागनाझव। तुवाखनाझव। तुविव। नहीर त्हदाविव। बोधि संटर या बदी संटर और यैंगछ निसद, निस बोधी आँगर के लगी दॉवी टोप पूरा, निसुट गन्डबाद लगी चाए हगर हो लेगागागों, पूरा गजागघर करनी वो बिगागे रहागागे वोडि को बगी निसुट है, वोधि संटर दीवागे और तो आद्टम्स at the corner, are not in touch, but atoms along the body diagonal are in contact with each other. We will have an admin present here, body centered. So this is very important, if you do not know the relation of A and R, at least this property you should know. In simple cubic unit cell, at the corner, atoms are in touch. In BCC, atoms along the body diagonal. उसके जोंगर येड़स. Now, when I ask you what is the relation of A and R. क्या हो जाए होता? ये रोगर के लेशे? Root 3. 2 pi root 3. See what did I say, atoms along the body diagonal. बोगर येड़स पाईंटर को तो क्या आता है? What is the body diagonal? विरेत भर खरद ततेए... विरोन लुए जाए हूँँ? विरोन विरोन कर्वाँ रहाँ तो अगर भार्द फराई रहाँ. जे वो वान ने जी है येजी आच्या है? एक बो़ी � involveर्दियाता है. विरोन येजी बो़ी ताने नहीं है येजी बो़ी नहीं है. �皂ट शीन, तो नोग किरची किवरीट ख़ूट षोट बनी विसकिस, नोग किरकिवरीट तराग cautious अपका बाञि 봐। रोग � Gewing सो द़ागा बहुँओ tota Editor उए amazing जर � combination of quicker क मंठा, तास पजेत बॉत यहобर्द È bike भूश then अब न। गरस दाखनियkeep यहसोँ jąome आतम एक लेग यह ळっちゃख और यह सुरजिक को चो ऐक किस बॉर दारनी का respostaन को जिय में दो थो TJ तो बॉत � frii उक ळद ये यह को चीि सुर्ख बर दाखत दाखने राइं के हाँ वहतो? तूगा बहुँक ये वहाँगु. तूगा वहुग के हाँगु जोगी आर्टन जाबई प्रज्एंचाए उसा ख़ूवग लेके आदरच्टेद लेके ये अडरपन जागगगगगगगग. तूगा यों आई मुऴ get edible पर लुई stupid तुम ज़ो भी अदन् जाबि've सकों than ये order ख烈 on येते कूओटाए तुम्मार हम जेओद करमन येराचानolut खे�λिया खृदपोस्ट़ल य 1080 त्रीट cats तो कुछ remember क्कचantically दिसं разбढ़ प्रछतेगगिcn ऑर बमीवे Plaza भी दष्खिएथ येर की� gr loft कुचानuely को eating चंमार श्खालेन करेiser त्रीट 2 into 4 by 3 pi r cube or we can write r is equals to root 3 by 4 into a so this equals to 2 into 4 by 3 pi r is root 3a by 4 cube divided by a cube this is the problem you have to solve it close your eyes and write this 0.6 exam is of course it is directly you should memorize this 3 is equal to 3 68.4% 68.4% what is the value of white fraction percent is white 31.6 31.6 or 32% sometimes in the exam they will give 68% you can consider that also 68% so white fraction is 32 or 31.6% you see the packing efficiency is better more than 52.4% it is a better way to arrange obviously you should do it extra item with the presenter one to the other what about you understood this now last one I will write down after this see this relation is very important it is a and r relation of all the unit cell first of all let me write a equals to 2 r and root 3 equals to 4 r next we will write down face centered cubic unit cell face centered cubic unit cell write down in this atoms are present at the face center along with along with atoms at corner ok the atoms along the face diagonal are in contact with each other the atoms along the face diagonal are in contact with each otherु.. ौK ौK ौK ौK ौK ् ौK ौK ौK ौK ौK ौK ौK ्チャンネル ौK ौK वईणराद ना सोते उरेठियट रद hmm तflanzen आह मो gehe ववेग 2010 कर लिए रमें, sites लिए वईणरा ஏर मैं सकता� drink अगर नोण से लोई ढ ہےट 2. 3. 6. 6 actually is a 6 of 1. 6 under unit面 and 6 outside. 6. 6. 1. 6. 6- 1. 6- 1. 6- 1. 6a- 1. 6a- 1. 6- 1. 6- 1. 1. जोग of 6 तो एक थोउ 7 Growth Ay Center तो कल स्Ag 9 तो तो क् love 10 lại 11 में� marvel � forever यह ज Beijing थो sleep but you have to imagine I will do it, I will draw the structure right I will structure it properly, you will understand we will see the arrangement and then you will understand it properly how it is being made, how the 5-12 atoms are being discussed we will discuss that in an element of atoms also you see this structure I am definitely drawing, you also draw this structure we have to discuss many things here FCC is the most important one for exam point of view FCC we also call it as CCP arrangement FCC, CCP are the same if the question says atoms A arranged in CCP manner it means the arrangement is FCC for A CCP is cubic most packing we will discuss that in arrangement of atoms so atoms at the corner is this 1, 2, 3, 4, 5 and face center of the atoms are present so this is the face center this is the face center of this or your friend colleague of face center will have somewhere here now one thing you see here this atom is in touch with 1, 2 and 3 this corner diagram 1, 2 and 3 similarly this edge if you extend here so here all the face center is in touch with basically you have to imagine how many faces are there with this corner you can draw in a crystal and that is not a unit cell here though this is only one unit cell we have how many faces you can draw with one corner in the entire unit cell so this A phase go if you extend this way here will be a face center like one more thing you will do corners is if you feel difficult to understand then you consider this atom how many atoms with which this atom is in touch you have face center atom this face center will be in touch with this one this one and this one means A-arga relation A-arga relation can be shown here A-arga relation can be shown here 2 A is equal to 4-arga if this relation is satisfied it means atoms are in contact A-center atom may, this face center उत्रुटरूँ. मैस dimeyam some space and space centre. अजा नेजा दिष्तलज अगा. �井aja-ajaja nenej that corner now I am writing on o. अजा नेजा या या दिष्तलज तेअ लिए io jahad chole jahad chole jahad chole jahad chole jahad chole jahad या जदिस्ोखा. oa jahad chole jahad. औजा या वे रूद. औजा प kilometre jahad chole jahad chole jahad chole jahad jahad this is what a by root 2 is it right and what is this again a by root 2 half of phase diameter a by root 2 or e i equal to what is it so this is the distance of kb means this is of this phase center and this phase center here is our distance root 2 root 2 means and we know root 2 is equals to what 4 dot okay so what we can say this atom are in touch what is this distance can tell me a by root 2 and we are trying to find out this distance this is a by root 2 and this is also a by root 2 what is this distance a by root 2 it should be a by root 2 touch yeah that's what i'm doing what is this distance k by root 2 when you find out this its not 90 because the angle is 60 all the angles are 60 then you can't apply it you can't apply it as you call this theorem oh yeah this is 60 right yeah you don't need to yeah right right right it is 60 this is also a by root 2 a by root 2 means what this 2 atoms are in contact right so the 2 atoms are in contact when the distance between them is a by root 2 if the distance between these 2 atoms is a by root 2 it means these are also in contact can we say that okay now to conclude this what we can say this phase center atom is in touch with all adjacent phase center opposite velocity pranidho this is in touch with that phase center this phase center and this phase center is it clear 2 distance a by root 2 yeah a by root 2 that is in touch with this corner let it be phase center it will be easy for you to understand you are trying to find out the correlation number okay corner atoms you can imagine and do that phase center atom if you are taking this is in touch with how many phase center atoms 1 2 3 4 1 2 3 4 understood this is in touch with this phase center this phase center this phase center this phase center which you have a phase center right 4 this 4 in this cube now extend all these phases so 4 is up okay or 4 4 plus 4 is 4 4 plus 4 is 4 sorry for this one