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the theoretical results of atomic parity non - conservation ( pnc ) when combined with the experimental results is an important probe of physics beyond the standard model of particle physics @xcite . there are two sources of pnc in atoms , nuclear spin - independent ( nsi ) and nuclear spin - dependent ( nsd ) . the nsi - pnc is well studied and experimentally observed in several atoms . the most precise measurement till date is in the case of atomic cs @xcite . the same experiment also indicated a signature of nsd - pnc effects . the most dominant source of which is the nuclear anapole moment ( nam ) , a parity odd nuclear electromagnetic moment arising from parity violating interaction within the nucleus @xcite . however , there are two other contributions to nsd - pnc , these are the nsd electron - nucleus @xmath3 exchange interaction and the combined effect of hyperfine interaction and nsi electron - nucleus @xmath3 exchange interaction .    the parameters describing nucleon - nucleon coupling , effect of nam is subsumed into it , extracted from the cs pnc experiment do not concur with the nuclear data @xcite . this certainly calls for the further investigation of the nsd - pnc effects in other atomic systems as well . an example of an alternative experiment is the proposal to measure the pnc in ba@xmath2 ion , suggested by fortson @xcite and is in progress at seattle @xcite . this experiment could lead to an unambiguous observation of nam in the @xmath4 transition , as the nsi - pnc alone does not contribute to this transition . it is important to note that the major difficulty to a clear observation of nam is the large nsi signal , which overwhelms the nsd signature . the ra@xmath2 ion has also been suggested and is considered to be an important candidate for the pnc measurement @xcite . apart from ba@xmath2 and ra@xmath2 ions which are one - valence systems the other promising candidate for pnc , the nam in particular , measurement is the atomic yb . an enhanced effect of pnc has already been reported @xcite in neutral yb , the @xmath5 transition , and for further refinement of the experiment is in progress at berkeley . the @xmath6 transition in yb@xmath2 , has also been suggested to reveal the nam signature and is being investigated at los alamos @xcite . the atomic theory results using reliable and accurate many - body methods are key to estimate the expected value of pnc transition amplitudes and extracting nam . for the theoretical calculations , the relativistic coupled - cluster ( rcc ) theory @xcite can be of great significance , as it is one of the most reliable many - body theory to incorporate electron correlation in atomic calculations . the rcc has been used extensively in atomic structure calculations @xcite of properties like transition energies , hyperfine structure constants , electromagnetic transition amplitudes , intrinsic electric dipole moment and pnc in atoms . apart from atomic physics , it has also been used with great success in nuclear @xcite , molecular @xcite and the condensed matter @xcite physics .    in this work , we employ perturbed relativistic coupled - cluster ( prcc ) theory to calculate nsi and nsd - pnc amplitudes of the @xmath06s\;^2s_{1/2}-[4f^{14}]5d\;^2d_{3/2}$ ] transition in the case of @xmath1yb@xmath2 ion . this is timely as there are few theoretical results , sahoo _ et al _ @xcite and dzuba _ et al _ @xcite for nsi - pnc and dzuba _ et al _ @xcite and porsev _ et al _ @xcite for nsd - pnc are the previous works . the nsi - pnc results from ref . @xcite calculated using rcc method differ substantially from ref . @xcite where the correlation - potential - method with sum - over - state approach is employed to calculate nsi and nsd - pnc . the nsd - pnc results reported in ref . @xcite are based on rpa and , in general , is in agreement with the results reported in ref . however , the later is based on the sum - over - state approach , at the level of pnc matrix elements . the prcc method @xcite employed in present work is different from the sum - over - states approach . it accounts for the all singly and doubly excited intermediate states . there are two sets of the cluster amplitudes in the prcc , and the summation over states in the first order time - independent perturbation is incorporated in one set of the cluster amplitudes . the paper is organized as follows . in section . [ method ] , we provide a brief description of the theoretical methods . the unperturbed rcc equations for close - shell and one - valence systems are given to serve as a easy reference . the perturbed rcc is then discussed in detail and prcc equations are derived . the expression for e1pnc using prcc wave function and some leading order diagrams are also discussed . results from the work and uncertainty estimates are presented and discussed in section . [ results ] . in absence of pnc interaction the atomic states are of definite parity , and we consider these as the eigen states of the no - virtual - pair dirac - coulomb hamiltonian @xcite @xmath7   \nonumber \\              &   & + \sum_{i < j}\frac{1}{r_{ij } } \lambda_+ ,    \label{dchamil}\end{aligned}\ ] ] where @xmath8 and @xmath9 are the dirac matrices , @xmath10 is the linear momentum , @xmath11 is the nuclear coulomb potential and the last term is the electron - electron coulomb interactions . the operator @xmath12 projects on the positive energy eigenstates to avoid the negative energy continuum solutions . the hamiltonian @xmath13 satisfies the eigen value equation @xmath14 where @xmath15 is the exact atomic state of the one - valence system and @xmath16 is the corresponding energy . here after , for compact notation , we use @xmath17 to represent @xmath13 . in the present work , we use rcc theory with the single and doubles ( ccsd ) excitation approximation to solve eq . ( [ hdc_eqn ] ) . in rcc , @xmath15 is expressed in terms of the closed - shell and one - valence cluster operators , @xmath18 and @xmath19 respectively , as @xmath20 |\phi_v\rangle ,   \label{psi_unptrb}\ ] ] where superscript @xmath21 represents the unperturbed rcc operators . the one - valence dirac - fock ( df ) reference state @xmath22 is obtained by adding an electron to the closed - shell reference state , @xmath23 . in the ccsd approximation , @xmath24 and @xmath25 . using the second quantized representation    @xmath26    here , @xmath27 and @xmath28 are the cluster amplitudes . the indexes @xmath29 ( @xmath30 ) represent core ( virtual ) states and @xmath31 represent valence states . the operators @xmath32 ( @xmath33 ) and @xmath34 ( @xmath35 ) give single and double replacements after operating on the closed(open)-shell reference states . the diagrammatic representation of these operators are shown in fig . [ ts_fig ] . the open - shell cluster operators are then the solutions of nonlinear equations @xcite    [ s0_eqn ] @xmath36    { \bar}{h}{_n}{s } \bar h_n s^{(0)}\ } |\phi_v\rangle    & = & e_v^{\rm att}\langle\phi_v^p|s^{(0)}_1|\phi_v\rangle ,    \label{s01_eqn }      \\    \langle \phi_{va}^{pq}|\bar h_n + \{\contraction[0.5ex ]    { \bar}{h}{_n}{s}\bar h_n s^{(0)}\ } |\phi_v\rangle    & = & e_v^{\rm att}\langle\phi_{va}^{pq}|s^{(0)}_2|\phi_v\rangle ,    \label{s02_eqn}\end{aligned}\ ] ]    where @xmath37 is the similarity transformed hamiltonian , @xmath38 is the normal ordered hamiltonian and @xmath39 is the attachment energy of the valence electron . the operators @xmath18 are the solutions of a similar set of nonlinear coupled equations    [ t0_eqn ] @xmath40    the details on the derivation of these equations are given in our previous work @xcite .    in presence of pnc interaction atomic states mix with the opposite parity states and the total atomic hamiltonian is @xmath41 here , @xmath42 is the perturbation parameter and @xmath43 represents the any general pnc interaction hamiltonian . it has two components , the nsi and nsd interaction . these are    @xmath44    where , @xmath45 is the fermi coupling constant , @xmath46 and @xmath47 are respectively the weak nuclear charge and the weak nuclear moment of the nucleus expressed in terms of neutron and proton numbers , @xmath48 and @xmath49 are the dirac matrices , @xmath50 is the normalized nuclear density and @xmath51 is the nuclear spin . compared to the nsi - pnc , the nsd - pnc require two important considerations because of the nuclear spin operator @xmath52 . first , the cluster operators in the electron space are rank one operators , and second , the atomic states in the one - valence sector are eigenstates of total angular momentum @xmath53 . similar to the unperturbed eigen value equation , eq . ( [ hdc_eqn ] ) , we may write the perturbed eigenvalue equation , satisfied by the total atomic hamiltonian , as @xmath54 where @xmath55 is the perturbed atomic state and @xmath56 is the corresponding energy . to the first - order in @xmath57 , @xmath58 and @xmath59 , where the bar in @xmath60 denotes it s parity is opposite to @xmath61 . from here on , to derive the prcc equations we consider the nsd - pnc interaction hamiltonian . using eq . ( [ hpnc_nsd ] ) , we can rewrite eq . ( [ ht_eqn ] ) as @xmath62 here , @xmath63 is the electronic part of @xmath64 . while writing above equation we have used @xmath65 , as @xmath64 is an odd parity operator it connects opposite parity states only . in the prcc theory , the perturbed wave function is expressed as @xmath66 \left [ 1      + s^{(0 ) } + \lambda \ps \cdot\mathbf{i } \right ] |\phi_v \rangle ,    \label{psi_ptrb}\ ] ] where @xmath67 and @xmath68 are the closed - shell and one - valence prcc operators , respectively . the superscript @xmath69 is used to indicate the perturbation . the diagrammatic representation of these cluster operators are shown in fig . [ pts_nsd_fig ] .    using eq . ( [ psi_ptrb ] ) in eq . ( [ ht_elc_eqn ] ) , we can rewrite the eigenvalue equation as @xmath70    \left [ 1 + s^{(0 ) } \right . \nonumber \\   & & \left . + \lambda\ps\cdot\mathbf{i } \right ] |\phi_v \rangle     = e_v e^{t^{(0 ) } } \left [ 1 + \lambda \pt\cdot\mathbf{i } \right ]      \left [ 1 + s^{(0 ) } \right . \nonumber \\   & & \left . + \lambda \ps\cdot\mathbf{i } \right ] |\phi_v \rangle.\end{aligned}\ ] ] to derive the prcc equations , we project the above equation on @xmath71 and retain the terms linear in @xmath42 . in addition , for further simplification , we use normal - ordered form of the hamiltonian @xmath72 . after these sequence of operations , the eigenvalue equation is modified to @xmath73      |\phi_v \rangle       \nonumber \\ = \left [ \delta e_v \ps + \delta e_v \pt ( 1 + s^{(0 ) } ) \right]|\phi_v        \rangle ,    \label{deltae1v}\end{aligned}\ ] ] where @xmath74 , is the correlation energy of the one - valence system . like @xmath75 introduced earlier , @xmath76 is the similarity transformed nsd - pnc interaction hamiltonian in the electronic space . the prcc equations of @xmath68 can now be derived by projecting eq . ( [ deltae1v ] ) with the excited determinants @xmath77 and @xmath78 as    @xmath79{}{h}{_{\rm n}}{s}\bar{h}_{\rm n }       \mathbf{s}^{(1 ) } \ } + \ { \contraction{}{h}{_{\rm n}}{s}\bar{h}_{\rm n }       \mathbf{t}^{(1 ) } \ } + \ { \contraction[0.5ex]{}{h}{_{\rm n}}{t }       \contraction[0.8ex]{}{v}{_{\rm n}t^{(1)}}{s}\bar{h}_{\rm n }       \mathbf{t}^{(1)}s^{(0)}\ } + \bar{\mathbf{h}}_{\rm elec}^{\rm nsd }       + \ { \contraction[0.5ex]{}{h}{_{\rm elec}^{\rm nsd}}{s }       \bar{\mathbf{h}}_{\rm elec}^{\rm nsd}{s}^{(0 ) } \}|\phi_v \rangle & = &    e_v^{\rm att } \langle \phi^p_v | \pso|\phi_v \rangle , \\    \langle \phi^{pq}_{vb}|\ { \contraction[0.5ex]{}{h}{_{\rm n}}{s}\bar{h}_{\rm n }       \mathbf{s}^{(1)}\}+\ { \contraction[0.5ex]{}{h}{_{\rm n}}{s}\bar{h}_{\rm n }       \mathbf{t}^{(1 ) } \ } + \ { \contraction[0.5ex]{}{h}{_{\rm n}}{t }       \contraction[0.8ex]{}{v}{_{\rm n}t^{(1)}}{s}\bar{h}_{\rm n }       \mathbf{t}^{(1)}s^{(0)}\ } + \bar{\mathbf{h}}_{\rm elec}^{\rm nsd }       + \ { \contraction[0.5ex]{}{h}{_{\rm elec}^{\rm nsd}}{s }       \bar{\mathbf{h}}_{\rm elec}^{\rm nsd}{s}^{(0 ) } \}|\phi_v \rangle & = &     e_v^{\rm att } \langle \phi^{pq}_{vb } | \pst|\phi_v \rangle .    \label{ccsptrb1v2}\end{aligned}\ ] ]    [ prcc_eqn ]    while deriving the equations we have used the relations @xmath80 and @xmath81 . these follows as @xmath67 is an operator of closed - shell sector , it does not contribute to the prcc equation of @xmath82 and @xmath83 . the closed - shell operators @xmath67 are the solutions of the similar set of coupled equations @xcite    [ pcceq ] @xmath84    these equations can be derived from the closed - shell perturbed eigenvalue equation . we can also derive a similar set of prcc equations for the nsi - pnc interaction hamiltonian . one major difference is , the cluster operators are rank zero operators .    after solving the rcc and prcc equations , we can use the atomic states for the properties calculations . the rcc expressions and the diagrams contributing to the hyperfine structure ( hfs ) constants and the e1 transition amplitudes are derived and discussed in our previous work @xcite . in the present work , we use the same expressions and diagrams to compute hfs constants and e1 transition amplitudes . the pnc induced electric dipole transition amplitude , using prcc wave function , is @xmath85 where @xmath86 is the dipole operator . this expression , unlike the conventional sum - over - sates approach , implicitly account for all the possible intermediate states . from eq . ( [ psi_ptrb ] ) , for the nsd - pnc interaction , the transition amplitude is @xmath87^\dagger \left [ 1          + s^{(0 ) } + \lambda \ps\cdot\mathbf{i } \right]^\dagger                             \nonumber \\         & & \mathbf{d } e^{t^{(0 ) } } \left [ 1 + \lambda \pt\cdot\mathbf{i } \right ]         \left [ 1 + s^{(0 ) } + \lambda \ps\cdot\mathbf{i}\right ] \red          \phi_v \rangle.\end{aligned}\ ] ] consider terms linear in @xmath42 and retain only those up to second order in cluster amplitude . define the electronic component as @xmath88 , corresponding to the @xmath89 , it is then given as @xmath90 to calculate @xmath91 , we use diagrammatic analysis to identify the goldstone diagrams from these terms . however , we exclude the structural radiation diagrams , arising from the terms involving two - body cluster operators , for example , @xmath92 . the selected diagrams from the leading order and next to leading order terms are shown in the fig . [ e1pnc_cc_fig ] . for all the calculations we use gaussian type orbitals ( gtos ) or single particle wave functions with @xmath93 potential . as mentioned earlier , to incorporate the relativistic effects we use the dirac - coulomb atomic hamiltonian . for the nuclear potential we consider the finite size fermi density distribution @xmath94 here , @xmath95 . the parameter @xmath96 is the half - charge radius , that is @xmath97 and @xmath98 is the skin thickness . the orbitals are of the form @xmath99 where @xmath100 and @xmath101 are the large and small component radial wave functions , @xmath102 is the relativistic total angular momentum quantum number and @xmath103 are the spinor - spherical harmonics . the radial components are then defined as linear combination of gaussian type functions @xcite @xmath104 the index @xmath105 , where @xmath106 is the number of basis functions and @xmath107 are the coefficients of linear combination . for large component we choose @xmath108 where @xmath109 is an integer and @xmath110 is the normalization constant . the small component are derived from the large components using kinetic balance condition . the @xmath111 follow the general relation @xmath112 the parameters , @xmath113 and @xmath9 , are optimized such that the single particle energies of the core and valence orbitals are in good agreement with the numerical results , obtained from grasp92 @xcite . in table . [ grasp_e_tab ] , we compare the energy of the valence orbitals from the gto with the grasp92 data . .the valence orbital and scf energies of gaussian type orbitals ( gto ) are compared with the grasp92 data . [ cols="^,^,^",options="header " , ]     [ nsi_orbital_tab ]    cccccccc & + d & @xmath114 & e1pnc & state & d & @xmath115 & e1pnc & state +   + & & & nsi - pnc & & & + @xmath116&@xmath117&@xmath118 & @xmath119&@xmath120 & @xmath121&@xmath122 & @xmath123 + @xmath124&@xmath125&@xmath126&@xmath127&@xmath128&@xmath129&@xmath130 & @xmath131 + @xmath132 & @xmath133 & @xmath134&@xmath135&@xmath136&@xmath137&@xmath130 & @xmath138 + @xmath139&@xmath140&@xmath141&@xmath142&@xmath143&@xmath144&@xmath145&@xmath146 +   + & & & nsd - pnc & & & + @xmath116&@xmath147&@xmath148 & @xmath119&@xmath120 & @xmath149&@xmath122 & @xmath123 + @xmath124&@xmath150&@xmath126&@xmath127&@xmath128&@xmath151&@xmath130 & @xmath131 + @xmath132&@xmath152&@xmath134&@xmath135&@xmath136&@xmath153&@xmath130&@xmath138 + @xmath139&@xmath154&@xmath141&@xmath142&@xmath143&@xmath155&@xmath156&@xmath146 +    [ nsi_orbital_df ]      for the nsd - pnc , the dominant contributions from various prcc terms in eq . ( [ e1pnccc1v ] ) are listed in table . [ nsi_comp_tab ] . for hyperfine transitions @xmath157 and @xmath158 , like in nsi - pnc , @xmath159 is the leading order term . it contributes about 231% and -130% , respectively . for transition @xmath160 , however , @xmath161 is the dominant term , contributing about -123% of the total value . the same trend is reported in ref . @xcite , where the contributions are about 252% , -226% and -157% , respectively , for the @xmath157 , @xmath162 and @xmath158 transitions . the next leading order term , @xmath161 , contribute about -114% and 35% , respectively to the @xmath157 and @xmath158 transitions . however , the second leading order term is @xmath159 for the @xmath162 transition , it contributes about 69% . the next two leading order terms are @xmath163 and @xmath164 . the contributions from these terms , in the sequence listed in table . [ nsi_comp_tab ] , are 39% , 11% and -22% , and -24% , -59% and -4% , respectively . non - negligible contributions are also observed from the terms @xmath165 , @xmath166 and @xmath167 .    unlike nsi - pnc , in nsd - pnc @xmath168 states also contribute to the e1pnc matrix element . in table . [ nsd_orbital_tab ] , we list dominant contributions from odd parity @xmath169 and @xmath168 states in the prcc calculations for the @xmath157 transition , and specifically the contributions from @xmath159 , @xmath161 and @xmath163 . at df level we present the contributions from the @xmath169 states in table . [ nsi_orbital_df ] . as we see in these tables , both at df and prcc levels , the dominant contribution is from the @xmath170 state . the total contribution from this in the prcc calculations is about 150% , which can be attributed to the 230% and -79% contributions from @xmath159 and @xmath161 , respectively . the large contribution through @xmath159 is due to the strong @xmath43 mixing with @xmath171 . however that is not the case with @xmath172 , which contributes through @xmath161 . at df level @xmath170 contributes only through mixing with @xmath171 , and contribution is about 214% . the state @xmath173 is the third most dominant contributing one , contributing about -40% , through @xmath43 perturbed @xmath172 . the other higher energy orbitals have negligible contribution . the nsd - e1pnc total results are given in table . [ e1pnc_tab ] . for comparison we have listed the df contributions . our df results @xmath174 , @xmath175 and @xmath176 for the three hyperfine transitions listed in table . [ e1pnc_tab ] compare well with the results @xmath177 , @xmath178 and @xmath179 , reported in ref . our total results , however , are on the higher side of the random - phase approximation ( rpa ) based results from ref . @xcite for all hyperfine transitions . the other theoretical nsd - pnc data available for comparison is from dzuba et al @xcite using the correlation - potential - method . our results for transitions @xmath157 and @xmath158 are in good agreement with their results . for transition @xmath162 , however , our result is higher than their value . ccccccccccc & & orbital & & orbital + d & @xmath180 & e1pnc & d & @xmath181 & e1pnc & & d & @xmath182 & e1pnc & + @xmath116 & @xmath183 & @xmath184 & @xmath185 & @xmath186 & @xmath187 & @xmath119 & @xmath120 & @xmath188 & @xmath189 & @xmath123 + @xmath124 & @xmath190 & @xmath191 & @xmath192 & @xmath193 & @xmath136 & @xmath127 & @xmath128 & @xmath194 & @xmath130 & @xmath131 + @xmath132 & @xmath195 & @xmath196 & @xmath197 & @xmath198 & @xmath130 & @xmath135 & @xmath136 & @xmath199 & @xmath130 & @xmath138 + @xmath139 & @xmath200 & @xmath201 & @xmath202 & @xmath203 & @xmath204 & @xmath142 & @xmath143 & @xmath205 & @xmath206 & @xmath146 + @xmath207 & @xmath208 & @xmath209 & @xmath210 & @xmath211 & @xmath212 & @xmath213 & & & & + @xmath214 & @xmath215 & @xmath216 & @xmath217 & @xmath218 & @xmath120 & @xmath219 & & & & + @xmath220 & @xmath221 & @xmath222 & @xmath223 & @xmath224 & @xmath204 & @xmath225 & & & & +   + @xmath226 & @xmath227 & @xmath189 & @xmath228 & @xmath229 & @xmath230 & @xmath231 & @xmath130 & @xmath130 & @xmath189 & @xmath232 + @xmath233 & @xmath234 & @xmath189 & @xmath235 & @xmath236 & @xmath196 & @xmath237 & @xmath238 & @xmath239 & @xmath189 & @xmath240 + @xmath241 & @xmath242 & @xmath189 & @xmath243 & @xmath244 & @xmath141 & @xmath245 & @xmath246 & @xmath247 & @xmath189 & @xmath248 + @xmath249 & @xmath250 & @xmath189 & @xmath251 & @xmath252 & @xmath201 & @xmath253 & @xmath254 & @xmath255 & @xmath256 & @xmath257 + @xmath210 & @xmath258 & @xmath189 & @xmath259 & @xmath260 & @xmath261 & @xmath262 & & & & + @xmath263 & @xmath264 & @xmath189 & @xmath265 & @xmath266 & @xmath204 & @xmath267 & & & & + @xmath268 & @xmath269 & @xmath189 & @xmath270 & @xmath271 & @xmath189 & @xmath272 & & & & +    [ nsd_orbital_tab ]    cccc transition & & other works + & df & prcc & + nsi - pnc & & & + @xmath273 & @xmath274 & @xmath275 & @xmath276 +   + nsd - pnc & & & + @xmath277 & @xmath174 & @xmath278 & @xmath279 + @xmath280 & @xmath175 & @xmath281 & @xmath282 + @xmath283 & @xmath176 & @xmath284 & @xmath285    @xmath286 reference@xcite . @xmath287 reference@xcite . @xmath288 reference@xcite . [ e1pnc_tab ]      to calculate the uncertainty of our e1pnc results we resort to a analysis based on the sum - over - state approach . in this method , the net uncertainty associated with an intermediate state is @xmath289 where @xmath290 and @xmath291 are the deviations of excitation energy and e1 matrix element form the experimental data . and these are calculated based on results presented in tables . [ ee_tab ] and [ e1_tab ] , respectively . for @xmath292 , uncertainty associated with @xmath43 matrix , we resort to the deviation of @xmath293 from experimental data , where @xmath294 and @xmath295 represent the magnetic dipole hyperfine constants of initial and final states of the e1pnc transition .    as discussed earlier , dominant contribution to nsi - pnc is from the @xmath170 state , which contributes through @xmath159 i.e. @xmath43 matrix element @xmath296 , @xmath297 matrix @xmath298 and energy denominator @xmath299 . the uncertainty associated with @xmath43 matrix element , we get using our rcc results for hyperfine constants , is 9.1% . and , the relative uncertainty of @xmath297 matrix element and the energy denominator are calculated as 5.7% and 3.4% , respectively . combining these , the net uncertainty in nsi - pnc result is 18.2% .    for nsd - pnc as well @xmath170 is the dominant contributing state . however in this case unlike nsi - pnc , apart from @xmath159 , contribution through @xmath161 is not negligible . the matrix elements involve in this case are @xmath300 and @xmath301 , and the energy denominator is @xmath302 . using the similar analysis we get 4.52% , 11.26% and 2.41% , respectively for @xmath292 , @xmath291 and @xmath303 . combining these , we get 18.19% as the net uncertainty associated with term @xmath161 . the @xmath304 relative uncertainty in nsd - pnc results are then 18.17% . in this work , we present nsi and nsd - pnc transition amplitudes for the @xmath06s^2\;s_{1/2 } - [ 4f^{14}]5d^2\;d_{3/2}$ ] transition in @xmath1yb@xmath2 ion . to estimate the uncertainty of the the pnc results , we also calculate excitation energies , hyperfine structure constants and e1 transition amplitudes for some of the important low lying states , using rcc theory . the e1pnc results are computed using prcc theory , which is formulated based on rcc theory and it incorporates electron correlation effects arising from a class of diagrams to all order in the presence of pnc interaction as a perturbation . our results for excitation energies , hyperfine structure constants and e1 transition amplitudes are in good agreement , in some cases better , with the previous experimental data . our nsi - pnc result lies between the results from two previous studies reported in refs . @xcite and @xcite . the nsd - pnc df results from our work is in excellent agreement with the results reported in ref . @xcite for all hyperfine transitions . the total nsd - 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we present nuclear spin - independent and dependent parity non - conservation amplitudes for the @xmath06s\;^2s_{1/2}-[4f^{14}]5d\;^2d_{3/2}$ ] transition of @xmath1yb@xmath2 , calculated using perturbed relativistic coupled - cluster theory . as a proxy to estimate theoretical uncertainty of these results we calculate the excitation energies , hyperfine structure constants and e1 transition amplitudes for the important low lying states . 
 the pnc results presented in paper shall be useful in the propose pnc experiments .