Electrical Engineering questions and answers. Its atomic mass is 39 g/mole. Here is step by step on how to compute K-nearest neighbors KNN algorithm: Determine parameter K = number of nearest neighbors. Nearest neighbour distance in bcc unit cell is greater than that of fcc having same edge length. r = nearest neighbor distance. That’s the theoretical maximum number of NNs possible–each of those NNs contributes a bond, giving the crystal structure very high stability. Such random particle movements when repeated. 248 nm and 0. In bcc lattice the corner atoms are called as the nearest neighbours and also a bcc structure has 8 corners atoms, so the pottassium atom will have 8 nearest neighbours. How many nearest neighbors does each particle in the face-centered cubic structure have? The coordination number of atoms in fcc lattice 12 and hence the number of nearest neighbours is 12 around each particle in face centered cubic lattice. type and ε 0 the energy at the equilibrium distance. = 42× 3a. 47. Correct option is B) In bcc lattice the corner atoms are called as the nearest neighbours and also a bcc structure has 8 corners atoms, so the potassium atom will have 8 nearest neighbours. Here’s the best way to solve it. The number of nearest neighbors and the next nearest neighbors are, _______ respectively. 5. 564×10−7cm)# # Number#of#atoms#in#the#cubic#unit#cell:# N u =8× 1 8 +6× 1 2 +4=8## (Eightonthecorners,sharedwith8neighbors+6onthefaces,eachonesharedwitha#. b) Calculate the unit cell volume of FCC Pt. Ans: d-d1-d2 = 0. 74. Here a a is the length of a side of the unit cell and R R is the radius of the atom the cell consists of. But this layer is slightly shifted and hence just filling the gaps of the first layer (B). In a bcc structure, for any atom at the corner of the lattice, nearest neighbour is at the centre of the lattice which is at a distance ofThe second nearest neighbour isat the adjacent corners of the lattice at a distance of a. b O av 3/2 . Q 5. View Solution. 9 pm. Continue reading. The symmetry is the same as the canonical BCC. Like. Their nearest neighbour distances in terms of a/R a / R are 2 2–√ 2 2. Since each fluoride ion has four nearest-neighbor calcium ions, the coordination in this structure is described as (8:4). In BCC, there will be atoms at the body centre and at corners. g. (i) Make a table of Nn and rn for n 1 to 6 for cubic I and F Bravais lattices. 1 (a), (b), and (c), in comparison. 707 a$. e. Medium. ##Recall#that#1#nm=# 1×10−7#cm. How long does. Bihar Board. The radius of the sodium atom is approximately :-12. The nearest neighbour distance dis the same as the distance from. There are 12 nearest atom in this unit cell. Step by step video, text & image solution for Statement -1:Distance between nearest neighbour in bcc is greater than that of fcc having same edge length. Solution The correct option is A √3 2 Nearest neighbour distance in BCC crystal (r+r−) = √3 a 2 Nearest neighbour distance in FCC crystal (r+r−) = √2 a 2 Given: Edge length. The distance between the two center atoms = parameter of the bcc lattice i. View solution > Sodium metal crystallizes in a body-centered cubic lattice with a unit cell edge of 4. neighbours and the nearest neighbour distance for either a BCC or FCC structure. Starting at the atom in (0,0,0), the nearest atom is in the x-direction, in the y-direction, and in the z-direction. for simple cubic and BCC unit cell along with nearest neighbour distance. Question: 3. (4) (4) a 2. 0016 g cm^(-3) ? 03:32. 6802 a fraction a u S 3 4 a radius SC 74% 68% 52%. Complete the following questions for 1) simple cubic (SC) lattice, 2) body-centered cubic (BCC) lattice, 3) face centered cubic (FCC) lattice and 4) diamond crystal structure. You can use it to look for nearby towns and suburbs if you live in a metropolis area, or you can search for cities. ) Assume that a hypothetical BCC Pt crystal has the same mass density as FCC Pt. ∴ Coordination Number = 6 Thus, the length of first nearest atom is, (1) → l (First nearest neighbour distance) The second nearest atom will be at the face diagonal 'C'. In this video I discussed Trick to calculate Nearest neighbour distance & coordination number for simple cubic structure. Question: 3. Highlight the nearest neighbors of a corner atom. Show transcribed image text. The distance between the two nearest neighour is The distance between the two nearest neighour is ASince the number of atoms in a single unit cell of Zn and S is the same, it is consistent with the formula ZnS. My textbook has given data for third and fourth nearest neighbours to be 12 and 8 with distances $sqrt{2}a$ and $frac{sqrt{11}a}{2}$. 25330 Note: • expect sum of 1/rn to converge rapidly for large n • A12 is dominated by the nearest neighbours (10 in FCC, HCP, 8 in BCC), but more distant neighbours affect A6 4. 912Å at room temperature. These are situated a distance r 0 central blue atom. 6 8Trick to calculate Nearest neighbour distance and coordination number in Bcc // solid state class 12. 414 * a. 9 p m. E. The centres of four vertical faces are another nearest lattice points. Third, the neighbor is the center of the next adjoining cell shared by two corners of your section. Copper lattice With a unit length of 361 pm U is the of copperA solid has 'BCC' structure. How many 3 nearest Neighbours are in the FCC? The nearest neighbors of any apex. give a relationship between nearest neighbour distance(d),radius of atom(r), edge of unit cell(a), for fcc and BCC crystal. The nearest distance is the distance between centre of these atoms. In sodium chloride structure, each N a+ ion is surrounded by six Cl− ions as nearest neighbours and _______ N a+ ions as next nearest neighbours. The cutoff distance was selected so that the distance is longer than the second nearest neighbor distance of Ti, an element with the longest nearest neighbor distance among V, Cu, Mo, and Ti. g. Not yet answered Marked out of 1 2 سؤال 2 The nearest neighbor distance in case of bcc structure of side a is: . Step 3. Second nearest neighbors are the neighbors of the first neighbors. 0k points) class-12Sodium has a bcc structure with the nearest neighbor distance 3 6 5. 86 0. (1), one can find the nearest neighbour distance at pressure P and temperature T. Twelve Na+ at a distance of √2 r (as the next nearest neighbour) Eight Cl- at a distance of √3 r 9as the third nearest neighbour) Six Na+ at a distance of √4 r or 2r (as the fourth nearest neighbour). See Answer See Answer See Answer done loading. algorithm {‘auto’, ‘ball_tree’, ‘kd_tree’, ‘brute’}, default=’auto’ Algorithm used to compute the nearest neighbors: ‘ball_tree. 11 Å) Body-centered with Edges and Faces. Let r n be the distance to the nth nearest neighbor expressed as a multiple of the nearest neighbor distance (e. View solution. 2 Equilibrium SeparationA 4Å A B A B A A B A 4Å A B Note: The atoms are the same size and touch each other by the hard sphere approximation. We could solve this with a series of Pythagorean Theorems from different perspectives, like I did when calculating the lattice parameter for a BCC unit cell, but this is an advanced topic. Hence, it will have 6 nearest atom to it in simple cubic. How many atoms are in the primitive unit cell of graphite? 5. The crystal structure of aluminium isQ4. 43 °A, calculate: (a) the distance from the center of one silicon atom to the center of its nearest neighbor, (b) the number density. It could be seen that the SIA (atom D) deviates from its original interstitial site at the GB, and atom A moves to position A′ by 1. Starting at the atom in (0,0,0), the nearest atom is in the x-direction, in the y-direction, and in the z-direction. 27, has a distorted close-packed structure. An element occurs in the body centered cubic lattice with a cell edge of 300 pm. Step by step video & image solution for A metal X has a BCC structure with nearest neighbor distance 365. View solution > View more. Here, the corner atoms and the face-centre atoms are in contact along the face diagonal. The nearest neighbors of any apex in FCC are the atoms in the middle of a face. (ii) Repeat for the tetragonal P and I Bravais lattices, assuming that c / a = 1. 5064 Å. •While for HCP Co, the lattice constants a and c are 2. F. Nearest neighbour distance in bcc unit cell is greater than that of fcc having same edge length. BCC 8 6 1. 52 Å. Its atomic weight is 39. Here a a is the length of a side of the unit cell and R R is the radius of the atom the cell consists of. 15. View solution. Potassium had body centred cubic structure with the nearest neighbour distance 260 √ 3 p m. The Nearest Neighbor rule is a well-known classification me-thod largely studied in the pattern recognition community, both for its simplicity and its performance. There are eight first nearest neighbors, six second nearest. Radius of atom in bcc(r)$ = dfrac{{sqrt {3a} }}{4}pm$ Where a is the edge length of the atom The second closest neighbor is at the separation of a. Option 4) 8, 12. because Statenemt -2: fcc has greater packing than bcc. 235 nm. Medium. There are eight first nearest neighbors, six second nearest neighbors, twelve third nearest neighbors, and eight fourth nearest neighbors for the central lattice √ point √ in the. H. In terms of the atomic radius, R, determine the distance between the centers of adjacent atoms for the BCC crystal structure along the [110] direction. 03:44. And there are $8$ such atoms, at a distance $(a√2)/2 = 0. If a distance between two nearest atoms is 3. The calculated lattice constants of bcc V-Mo, bcc V-Ti, and hcp V-Ti solid solution phases are presented in Fig. Q. The distance between nearest neighbour is: Q. My textbook has given data for third and fourth nearest neighbours to be 12 and 8 with distances $sqrt{2}a$ and $frac{sqrt{11}a}{2}$. What is the distance between nearest. Reason Bcc has greater packing efficiency than fcc. The first three nearest neighbor distance for primitive cubic lattice are respectively (edge length of unit cell = a): A. 5× 3)A˚. ∴ Distance between two atoms. Since each fluoride ion has four nearest-neighbor calcium ions, the coordination in this structure is described as (8:4). Option 1) 12, 6. The next neighbors are in the center of the cube, and there are $8$ such atoms, at a distance $(a√3)/2 = 0. Consider the lattice point at the centre of the top face of an FCC unit cell. how many nearest and next nearest neighbours respectively each potassium has in BCC lattice. This is incorrect. Its atomic weight is 39 . How many atoms of the element does 208 g of the element contain. Solution. 23 26 Metallic is explained by Diffusion of ions (O Excitation of free electrons Oscillation of positive ions Existence of bcc al I attic. Caleulate its density 13. $endgroup$ – user93237. Question: iron forms a bcc lattice with a density of 7870 kg/m^3. 540 A° in FCC-iron. 52 ∘ A. 0 g cm −3 . The nearest neighbor distance is 0. 9 p m. e, the co-ordination number is 6 (which is the number of nearest neighbours of an atom in a crystal). Show transcribed image text. What is metal X if its density is 1. 02:17. 2) 2 1 = 0. And there are $8$ such atoms, at a distance $(a√2)/2 = 0. Its density will be (K=39,N A=6×10 23) Medium. Eduncle Best Answer. •each sphere touches 12 equidistant nearest neighbors (CN = 12). Problem #2 bcc: one conventional cell has two sites (twice as large as a primitive cell) fcc: one conventional cell has four cites (1 conventional cell=4 primitive cells) Simple cubic . Interstitial Sites in the Basic Crystal Structures (SC,. If k = 1 (the default), the return value is a numeric vector v such that v[i] is the nearest neighbour distance for the ith data point. Plan Your Route allows you to enter a start and end destination and receive the shortest route (as determined by Google) with step-by-step instructions. , in a simple cubic Bravais lattice r 1 = 1, r 2 = √2 = 1. fcc lattice with a = 5? nearest neighbor distance a 5? = 2 = 2 =4? 2 2 view direction. In a bcc structure, for any atom at the corner of the lattice, nearest neighbour is at the centre of the lattice which is at a distance of The second nearest neighbour is at the. So for BCC let's consider the atom at the body centre, for this atom the atom at the corner are. Continue reading. Medium. First, you can obtain CIF-file from COD, then load it with Olex2 (free, available on Windows, Linux, MacOS) and execute command envi <r>, which will print a list of the atoms about special position within a sphere of radius r r. [(4 / 3) π] − 1 / 3 Γ [(3 n + 1) / 3] − 1 f f 0 2 n / (2 n + 1) where 〈H n 〉 is the mean nth nearest-neighbor distance,. Note that the nearest-neighbor distance corresponds to the atomic bond length. For face centred cubic lattice nearest neighbour distance is half of the face diagonal distance, a√2/2. of atom touching a particular atom in the given unit cell is known as coordination number and that atoms are known as nearest neighbour. All calculations were done with the LAMMPS [18] and an in-house MD code, KISSMD [19]. . I have found the number of first , second and th. 414). Say you are sitting in the center of a cell. Calculate the density (in units of g/cm3) of Si and GaAs from the lattice constants, atomic weights, and Avogadro's number. Second neighbours are at the centers of the nearest adjacent cells. AgCl,. >. The crystal structure of pyrite is primitive cubic, and this is reflected in the cubic symmetry of its natural crystal facets. Option 2) 6, 12. When you are looking for the smallest nearest neighbour distance this means that you are looking for the smallest a a in an FCC or HPC packing. Prob. Q. The NaCl structure can be regarded as two interpenetrating FCC lattices. 0 3 6, N A = 6 × 1 0 2 3, K = 3 9) Hard View solutionExpert-verified. This source says that the interplanar spacing of the (111) ( 111) plane in FCC is a 3√ a 3, which is in agreement with the formula above. Nearest neighbour distance in bcc unit cell is greater than that of fcc having same edge length. First closest neighbor is eight (molecules at corner)and The Second closest neighbor is six. ] (b) Iron has the bond-centered-cubic (BCC) crystal lattice and its density is 7. Answered by Varsha | 25 Jan, 2019, 11:43: AMPotassium has a bcc structure with nearest neighbour distance of 4. IIT JEE & NEET video lectures by nucleon KotaDownload app to watch videos prepared in Kota classrooms by IITian educators with. Each Ca + ion has 6 Cs + ions as the next nearest neighbour at a distance of r = d Cl-Cl-. Figure 3 shows that, if only first-nearest neighbors are considered in the analysis, the binding energies are significantly underestimated (by 53 pct in bcc and 20 pct in fcc) compared to the value for 500 nearest-neighbor shells. Each sphere in a cP lattice has coordination number 6, in a cI lattice 8, and in a cF lattice 12. This feature also. Therefore, for a BCC lattice there are eight (8) nearest neighbors for any given lattice point. So for BCC let's consider the atom at the body centre, for this atom the atom at the corner are nearest. function of the interatomic distance, (a) Using the Lennard-Jones potential, calculate the lattice constants of the fcc, hcp, and bcc crystals at zero pressure and temperature. Let r n be the distance to the nth nearest neighbor expressed as a multiple of the nearest neighbor distance (e. calculate the nearest-neighbor distance d_nn, and the length of the conventional crystal unit cell,a. a) Calculate the nearest-neighbor distance in FCC Pt. Coordination number = 6 Simple Cubic (SC) Structure •Coordination number is the number of nearest neighbors •Linear density (LD) is the number of atoms per unit length along a specific crystallographic direction a1 a2 a3 . Can you explain this answer? defined & explained in the simplest way possible. The face-centered cubic (fcc) has a coordination number of 12 and contains 4 atoms per unit cell. Let's start from any apex of the elementary cubic cell. 52{A^ circ } $ Therefore, a = $ dfrac{{4. 12. Hence, it will have 6 nearest atom to it in simple cubic. 707 a$. In the fcc crytsal lattice, the atoms are present at corners of the cube and at the face-centres of the cube. Calculate its density - (A s s u m e m a s s o f s o d i u m = 2 3 g / m o l) Medium. Correct option is B) In bcc lattice the corner atoms are called as the nearest neighbours and also a bcc structure has 8 corners atoms, so the potassium atom will have 8 nearest neighbours. In this video I discussedTrick to calculate Nearest neighbour distance and coordination number in Bcc // solid state class 12. 2 g/cm'. British Columbia (Canada) Driving Distance Calculator, calculates the Distance and Driving Directions between two addresses, places, cities,. 2 Ao. 757*10^30 amu/m^34. g. Potassium has a body-centered cubic structure with the nearest neighbour distance 452 p m. 73 A, the edge length of the cell is: Hard. 最近傍探索（英: Nearest neighbor search, NNS ）は、距離空間における最も近い点を探す最適化問題の一種、あるいはその解法。 近接探索（英: proximity search ）、類似探索（英: similarity search ）、最近点探索（英: closest point search ）などとも呼ぶ。 問題はすなわち、距離空間 M における点の集合 S があり. In this video I discussedTrick to calculate Nearest neighbour distance and coordination number in Bcc // solid state class 12. A metal crystallizes in two cubic phases, face centered cubic (fcc) and body centered cubic (bcc) whose unit cell length are 3. Each value has a full citation identifying its source. The correct answer is: a Sodium has bcc packing. Using the Pythagorean theorem in 3D, we get: a^2 + a^2 + a^2 = d^2 3a^2 = d^2 d = a * sqrt(3) = 1. The diagram shows the unit cell of a body-centered-cubic crystal. 14 Draw cubes showing four {111} planes and four. Is equal to a Underwood 3, 12 and rode three. Medium. n th nearest neighbor expressed as a multiple of the nearest neighbor distance (for. Bihar Board. Interplanar cystal spacing of cubic crystal families is defined as. (a) Show that at the equilibrium separation R 0 U(R 0) = 2Nq2(1 1=n)ln2 R 0: (1) (b) Let the crystal be compressed so that R 0!RThe coordination number and distance between nearest neighbour in BCC structure is Option 1) 6 , Option 2) 8 , Option 3) 6 , Option 4) 8 ,. What is this ratio using the energies from the nearest. Reason Bcc has greater packing efficiency than fcc. Cesium chloride (CsCl) (a = 4. I have calculated the effective number of atoms in a single unit cell of FCC. The next neighbors are in the center of the cube, and there are $8$ such atoms, at a distance $(a√3)/2 = 0. Note that the nearest-neighbor distance corresponds to the atomic bond length. 866 a and c2 = 6 next-nearest neighbours at a distance of dc2 = a ≈ 2. Therefore the ratio between cationic and anionic radii in zinc blend is 0. Thus, the nearest-neighbor distance is: d = r * sqrt(2) (b) For the BCC crystal along the [111] direction, there are four atoms per unit cell along this direction. 52 Å. we see that there are 8. Second nearest-neighbor modified embedded atom method potentials for bcc transition metals Byeong-Joo Lee, 1, * M. a 1, a 2, a 3, a 4 are coefficients of any 4 consecutive terms in the expansion of (1 + x) n, then a 1 a 1 + a 2 + a 3 a 3 + a 4 =Thus, the nearest-neighbor distance is: d = r * sqrt(2) (b) For the BCC crystal along the [111] direction, there are four atoms per unit cell along this direction. Now, for a bcc unit cell, the relationship between r and a (edge-length) is: r = √ 3 4 a. 3 r 1. Statement 2: FCC has greater packing efficiency than BCC. Question: Q2. A lattice constant or lattice parameter is one of the physical dimensions and angles that determine the geometry of the unit cells in a crystal lattice, and is proportional to the distance between atoms in the crystal. The arrangement of the atoms in a solid that has a simple cubic unit cell was shown in part (a) in Figure 12. ! The simple cubic has 1 lattice point per unit cell, with a total area of a3! Number of nearest neighbours: 6! Nearest neighbour distance: a! Number of next-nearest neighbours: 12! Next-nearest neighbour distance: √2a (prove this!) Simple cubic lattice (4/3)π(a/2)3 (a3) Packing fraction. Recommended Questions. iron forms a bcc. In sodium chloride structure, each N a+ ion is surrounded by six Cl− ions as nearest neighbours and _______ N a+ ions as next nearest neighbours. Its atomic mass is 39 g/mole. These are the nearest neighbours for the atom at the center. (D) Likes ( 0) Reply ( 0) T. If the unit cell length is 5. How many towns are within 45 miles of Victoria, British Columbia, Canada? There are 86 towns and cities for the specified radius with a minimum population of 5, we. Consequently, the simple cubic lattice is an inefficient way to pack atoms together in space: only 52% of the total space is filled by the atoms. of nearest neighbor is 8. The displacement of atom A is approximately equals to half of the neighbor distance along <111> direction in bcc lattice, so A′ is the split interstitial site. how many nearest and next nearest neighbours respectively each potassium has in BCC lattice What is the distance between next nearest Neighbour in BCC unit cells? For a body centered cubic (BCC) lattice, the nearest neighbor distance is half of the body diagonal distance, 23 a . Reason Bcc has greater packing efficiency than fcc. In the N a C l type structure shortest distance between two nearest neighbours is 100 pm, then the distance between two next nearest neighbours in the same unit cell will be: View Solution Q 5Let rn be the distance to the. 9 pm. Make a table of N n and r n for n = 1,. 52 Å`its atomic weight is `39` its density (in kg `m^(-3)`) will be asked Jun 17, 2019 in Chemistry by KumariPrachi ( 90. A solid has 'BCC' structure. How many atoms are in the primitive unit cell? Describe the unit vectors. In a body-centered cubic crystal, each atom has 8 nearest neighbors (NN). For a simple cubic lattice, it is clear that the nearest neighbor distance is just the lattice parameter, a. 5 ˚ A and 3. This is consistent with the packing density calculations reported in lecture that give FCC as being 74% dense and BCC 68% dense. Therefore, for a BCC lattice there are eight (8) nearest neighbors for any given lattice point. In bcc lattice the corner atoms are called as the nearest neighbours and also a bcc structure has 8 corners atoms, so the pottassium atom will have 8 nearest neighbours. Consequently for the middle particle (It will apply for the wide range of various too). Note that the nearest-neighbor distance corresponds to the atomic bond length Calculate the density (in units of g/cm3) of Si and GaAs from the lattice constants, atomic weights, and Avogadro's number. 543 nm. The first nearest atom for any atom in a cubic unit cell is the atom located at adjacent corner of it. 50 SC 6 12 1. Nearest neighbour to an atom (say at origin) is the atom present is the centre of theat point P and the position of P can be =The correct answer is: = The positions of number of nearest neighbours in a unit cell of bcc structure is given by:a)b)c)d)None of theseCorrect answer is. In bcc lattice the corner atoms are called as the nearest neighbours and also a bcc structure has 8 corners atoms, so the potassium atom will have 8 nearest neighbours. The conventional cell for the body centred cubic bcc. 314. This is incorrect. The ratio of the distances with the nearest neighbours in a body centered cubic (BCC) and a face centered cubic (FCC) crystals with the same unit cell edge. The four corners of this face are nearest neighbours to the central lattice point. 9 p m. View solution > The number of close neighbours in a body-centred cubic lattice of identical spheres is:. 52 ∘ A. Potassium has BCC structure with nearest neighbour distance (2. View Notes - HW440-1 from EE 440 at University of Texas. Since there are two lattice sites per bcc cubic cell, the density should be. >> The Solid State. Question 2 1 pts The 4th nearest neighbor distance in a BCC lattice that has a lattice parameter equal to a is Q v3 w/2 O 2a Question 3 1 pts The number of atoms per unit area on the closest packed plane in a BCC lattice that has a lattice parameter equal to a is O 1/8*2 O V2 /2a*2 Q 2/ 2 a*2 O v3/2a^2In the present video I have discussed details of Face centered Cubic Structure. Question: a) How many atoms are there in a simple cubic unit cell? in a bcc unit cell? in a fcc unit cell? in the unit cell characterizing the diamond lattice? b) In terms of the lattice constant a, what is the distance. r = 43a. In bcc: The atoms at the body diagonal touch each other. HOT. To find the nearest neighbour distances from one point pattern to another point pattern, use nncross. If its density (in g cm–3) would be X , then the value of ( 100 X − 1 10 ) is Potassium has a bcc structure with nearest neighour distance `4. Travelmath helps you find cities close to your location. First three nearest neighbour distance for body centred cubic lattice are respectively:Introduction of edge length and Calculation of coordination no. The La Fe distance is greater than Fe Fe and increases about 2. fcc unit cell (110) face. In transition metals, small foreign atoms usually sit on interstitial sites. radii of A and B atoms are then 1Ǻ number of A atoms per unit cell = 8 ⋅ 18 = 1 A number of B atoms per unit cell = 1 4Å volume of atoms per unit cell = 1 ⋅ 4π3 ⋅ (1Å)3 + 1 ⋅ 4π3 ⋅ (1Å)3. a) Calculate the nearest-neighbor distance in FCC Pt. What is metal X if its density is 1. I. g. View the full answer Answer. 4971 Å, and the ratio c/a equals 1. ADVERTISEMENT. , 6 for the fee, bcc, and sc Bravais lattices. 414). A rock containing three crystals of pyrite (FeS 2). Like. 097. r = 219. Get Distance & Directions. Example 16. $ dfrac{{asqrt 3 }}{2} $ = $ 4. Thus, the coordination number of fcc is 12. 18 16 : 57. The distance between them is diagonal−of−cube 2 = √3a 2 . The ratio of the distances with the nearest neighbours in a body centered cubic (BCC) and a face centered cubic (FCC) crystals with the same unit cell edge length is: Q. Minimum and maximum distance of a satellite from the center of earth are 2 R and 4 R respectively where R is radius of earth. And there are 8 such atoms, at a distance (a√2)/2=0. Therefore, for a BCC lattice there are eight (8) nearest neighbors for any given lattice point. Once again I do not understand where to even start with this!!! Here’s the best way to solve it. Number of atom per unit cell = 8 x 1/8 + 1 x 1 = 2 Number of atoms in - 8ghto4gg. Number of atom in unit cell of BCC (Z) = 2 Nearest neighbor distance, r = Atomic mass (M) = 39 g/mole Avogadro's number . Viewed 13k times. Its density would be (1 (5. A metal X has a BCC structure with nearest neighbor distance 365. 0 g cm −3 . In the body centred cubic lattice (bcc) the nearest neighbours touch along the body diagonal. BCC 8; FCC 12; HCP 12 .